Merge branch 'master' into master

.codeclimate.yml

@@ -1,11 +0,0 @@
----
-engines:
-  gofmt:
-    enabled: true
-  govet:
-    enabled: true
-  golint:
-    enabled: true
-ratings:
-  paths:
-  - "**.go"

.gitignore

@@ -1,2 +1,3 @@
 documents
+coverage.txt
 _book

README.md

@@ -4,10 +4,11 @@ The fantastic ORM library for Golang, aims to be developer friendly.
 
 [![go report card](https://goreportcard.com/badge/github.com/jinzhu/gorm "go report card")](https://goreportcard.com/report/github.com/jinzhu/gorm)
 [![wercker status](https://app.wercker.com/status/8596cace912c9947dd9c8542ecc8cb8b/s/master "wercker status")](https://app.wercker.com/project/byKey/8596cace912c9947dd9c8542ecc8cb8b)
+[![codecov](https://codecov.io/gh/jinzhu/gorm/branch/master/graph/badge.svg)](https://codecov.io/gh/jinzhu/gorm)
 [![Join the chat at https://gitter.im/jinzhu/gorm](https://img.shields.io/gitter/room/jinzhu/gorm.svg)](https://gitter.im/jinzhu/gorm?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
 [![Open Collective Backer](https://opencollective.com/gorm/tiers/backer/badge.svg?label=backer&color=brightgreen "Open Collective Backer")](https://opencollective.com/gorm)
 [![Open Collective Sponsor](https://opencollective.com/gorm/tiers/sponsor/badge.svg?label=sponsor&color=brightgreen "Open Collective Sponsor")](https://opencollective.com/gorm)
-[![MIT license](http://img.shields.io/badge/license-MIT-brightgreen.svg)](http://opensource.org/licenses/MIT)
+[![MIT license](https://img.shields.io/badge/license-MIT-brightgreen.svg)](https://opensource.org/licenses/MIT)
 [![GoDoc](https://godoc.org/github.com/jinzhu/gorm?status.svg)](https://godoc.org/github.com/jinzhu/gorm)
 
 ## Overview
@@ -27,11 +28,11 @@ The fantastic ORM library for Golang, aims to be developer friendly.
 
 ## Getting Started
 
-* GORM Guides [http://gorm.io](http://gorm.io)
+* GORM Guides [https://gorm.io](https://gorm.io)
 
 ## Contributing
 
-[You can help to deliver a better GORM, check out things you can do](http://gorm.io/contribute.html)
+[You can help to deliver a better GORM, check out things you can do](https://gorm.io/contribute.html)
 
 ## License
 

association.go

@@ -267,15 +267,16 @@ func (association *Association) Count() int {
 		query        = scope.DB()
 	)
 
-	if relationship.Kind == "many_to_many" {
+	switch relationship.Kind {
+	case "many_to_many":
 		query = relationship.JoinTableHandler.JoinWith(relationship.JoinTableHandler, query, scope.Value)
-	} else if relationship.Kind == "has_many" || relationship.Kind == "has_one" {
+	case "has_many", "has_one":
 		primaryKeys := scope.getColumnAsArray(relationship.AssociationForeignFieldNames, scope.Value)
 		query = query.Where(
 			fmt.Sprintf("%v IN (%v)", toQueryCondition(scope, relationship.ForeignDBNames), toQueryMarks(primaryKeys)),
 			toQueryValues(primaryKeys)...,
 		)
-	} else if relationship.Kind == "belongs_to" {
+	case "belongs_to":
 		primaryKeys := scope.getColumnAsArray(relationship.ForeignFieldNames, scope.Value)
 		query = query.Where(
 			fmt.Sprintf("%v IN (%v)", toQueryCondition(scope, relationship.AssociationForeignDBNames), toQueryMarks(primaryKeys)),
@@ -367,6 +368,7 @@ func (association *Association) saveAssociations(values ...interface{}) *Associa
 	return association
 }
 
+// setErr set error when the error is not nil. And return Association.
 func (association *Association) setErr(err error) *Association {
 	if err != nil {
 		association.Error = err

callback.go

@@ -1,6 +1,6 @@
 package gorm
 
-import "log"
+import "fmt"
 
 // DefaultCallback default callbacks defined by gorm
 var DefaultCallback = &Callback{}
@@ -13,6 +13,7 @@ var DefaultCallback = &Callback{}
 //   Field `rowQueries` contains callbacks will be call when querying object with Row, Rows...
 //   Field `processors` contains all callback processors, will be used to generate above callbacks in order
 type Callback struct {
+	logger     logger
 	creates    []*func(scope *Scope)
 	updates    []*func(scope *Scope)
 	deletes    []*func(scope *Scope)
@@ -23,6 +24,7 @@ type Callback struct {
 
 // CallbackProcessor contains callback informations
 type CallbackProcessor struct {
+	logger    logger
 	name      string              // current callback's name
 	before    string              // register current callback before a callback
 	after     string              // register current callback after a callback
@@ -33,8 +35,9 @@ type CallbackProcessor struct {
 	parent    *Callback
 }
 
-func (c *Callback) clone() *Callback {
+func (c *Callback) clone(logger logger) *Callback {
 	return &Callback{
+		logger:     logger,
 		creates:    c.creates,
 		updates:    c.updates,
 		deletes:    c.deletes,
@@ -53,28 +56,28 @@ func (c *Callback) clone() *Callback {
 //       scope.Err(errors.New("error"))
 //     })
 func (c *Callback) Create() *CallbackProcessor {
-	return &CallbackProcessor{kind: "create", parent: c}
+	return &CallbackProcessor{logger: c.logger, kind: "create", parent: c}
 }
 
 // Update could be used to register callbacks for updating object, refer `Create` for usage
 func (c *Callback) Update() *CallbackProcessor {
-	return &CallbackProcessor{kind: "update", parent: c}
+	return &CallbackProcessor{logger: c.logger, kind: "update", parent: c}
 }
 
 // Delete could be used to register callbacks for deleting object, refer `Create` for usage
 func (c *Callback) Delete() *CallbackProcessor {
-	return &CallbackProcessor{kind: "delete", parent: c}
+	return &CallbackProcessor{logger: c.logger, kind: "delete", parent: c}
 }
 
 // Query could be used to register callbacks for querying objects with query methods like `Find`, `First`, `Related`, `Association`...
 // Refer `Create` for usage
 func (c *Callback) Query() *CallbackProcessor {
-	return &CallbackProcessor{kind: "query", parent: c}
+	return &CallbackProcessor{logger: c.logger, kind: "query", parent: c}
 }
 
 // RowQuery could be used to register callbacks for querying objects with `Row`, `Rows`, refer `Create` for usage
 func (c *Callback) RowQuery() *CallbackProcessor {
-	return &CallbackProcessor{kind: "row_query", parent: c}
+	return &CallbackProcessor{logger: c.logger, kind: "row_query", parent: c}
 }
 
 // After insert a new callback after callback `callbackName`, refer `Callbacks.Create`
@@ -93,7 +96,7 @@ func (cp *CallbackProcessor) Before(callbackName string) *CallbackProcessor {
 func (cp *CallbackProcessor) Register(callbackName string, callback func(scope *Scope)) {
 	if cp.kind == "row_query" {
 		if cp.before == "" && cp.after == "" && callbackName != "gorm:row_query" {
-			log.Printf("Registing RowQuery callback %v without specify order with Before(), After(), applying Before('gorm:row_query') by default for compatibility...\n", callbackName)
+			cp.logger.Print("info", fmt.Sprintf("Registering RowQuery callback %v without specify order with Before(), After(), applying Before('gorm:row_query') by default for compatibility...", callbackName))
 			cp.before = "gorm:row_query"
 		}
 	}
@@ -107,7 +110,7 @@ func (cp *CallbackProcessor) Register(callbackName string, callback func(scope *
 // Remove a registered callback
 //     db.Callback().Create().Remove("gorm:update_time_stamp_when_create")
 func (cp *CallbackProcessor) Remove(callbackName string) {
-	log.Printf("[info] removing callback `%v` from %v\n", callbackName, fileWithLineNum())
+	cp.logger.Print("info", fmt.Sprintf("[info] removing callback `%v` from %v", callbackName, fileWithLineNum()))
 	cp.name = callbackName
 	cp.remove = true
 	cp.parent.processors = append(cp.parent.processors, cp)
@@ -116,11 +119,11 @@ func (cp *CallbackProcessor) Remove(callbackName string) {
 
 // Replace a registered callback with new callback
 //     db.Callback().Create().Replace("gorm:update_time_stamp_when_create", func(*Scope) {
-//		   scope.SetColumn("Created", now)
+//		   scope.SetColumn("CreatedAt", now)
-//		   scope.SetColumn("Updated", now)
+//		   scope.SetColumn("UpdatedAt", now)
 //     })
 func (cp *CallbackProcessor) Replace(callbackName string, callback func(scope *Scope)) {
-	log.Printf("[info] replacing callback `%v` from %v\n", callbackName, fileWithLineNum())
+	cp.logger.Print("info", fmt.Sprintf("[info] replacing callback `%v` from %v", callbackName, fileWithLineNum()))
 	cp.name = callbackName
 	cp.processor = &callback
 	cp.replace = true
@@ -132,11 +135,15 @@ func (cp *CallbackProcessor) Replace(callbackName string, callback func(scope *S
 //    db.Callback().Create().Get("gorm:create")
 func (cp *CallbackProcessor) Get(callbackName string) (callback func(scope *Scope)) {
 	for _, p := range cp.parent.processors {
-		if p.name == callbackName && p.kind == cp.kind && !cp.remove {
+		if p.name == callbackName && p.kind == cp.kind {
-			return *p.processor
+			if p.remove {
+				callback = nil
+			} else {
+				callback = *p.processor
+			}
 		}
 	}
-	return nil
+	return
 }
 
 // getRIndex get right index from string slice
@@ -159,7 +166,7 @@ func sortProcessors(cps []*CallbackProcessor) []*func(scope *Scope) {
 	for _, cp := range cps {
 		// show warning message the callback name already exists
 		if index := getRIndex(allNames, cp.name); index > -1 && !cp.replace && !cp.remove {
-			log.Printf("[warning] duplicated callback `%v` from %v\n", cp.name, fileWithLineNum())
+			cp.logger.Print("warning", fmt.Sprintf("[warning] duplicated callback `%v` from %v", cp.name, fileWithLineNum()))
 		}
 		allNames = append(allNames, cp.name)
 	}

callback_create.go

@@ -31,7 +31,7 @@ func beforeCreateCallback(scope *Scope) {
 // updateTimeStampForCreateCallback will set `CreatedAt`, `UpdatedAt` when creating
 func updateTimeStampForCreateCallback(scope *Scope) {
 	if !scope.HasError() {
-		now := NowFunc()
+		now := scope.db.nowFunc()
 
 		if createdAtField, ok := scope.FieldByName("CreatedAt"); ok {
 			if createdAtField.IsBlank {
@@ -50,7 +50,7 @@ func updateTimeStampForCreateCallback(scope *Scope) {
 // createCallback the callback used to insert data into database
 func createCallback(scope *Scope) {
 	if !scope.HasError() {
-		defer scope.trace(NowFunc())
+		defer scope.trace(scope.db.nowFunc())
 
 		var (
 			columns, placeholders        []string
@@ -59,7 +59,7 @@ func createCallback(scope *Scope) {
 
 		for _, field := range scope.Fields() {
 			if scope.changeableField(field) {
-				if field.IsNormal {
+				if field.IsNormal && !field.IsIgnored {
 					if field.IsBlank && field.HasDefaultValue {
 						blankColumnsWithDefaultValue = append(blankColumnsWithDefaultValue, scope.Quote(field.DBName))
 						scope.InstanceSet("gorm:blank_columns_with_default_value", blankColumnsWithDefaultValue)
@@ -83,21 +83,30 @@ func createCallback(scope *Scope) {
 			quotedTableName = scope.QuotedTableName()
 			primaryField    = scope.PrimaryField()
 			extraOption     string
+			insertModifier  string
 		)
 
 		if str, ok := scope.Get("gorm:insert_option"); ok {
 			extraOption = fmt.Sprint(str)
 		}
+		if str, ok := scope.Get("gorm:insert_modifier"); ok {
+			insertModifier = strings.ToUpper(fmt.Sprint(str))
+			if insertModifier == "INTO" {
+				insertModifier = ""
+			}
+		}
 
 		if primaryField != nil {
 			returningColumn = scope.Quote(primaryField.DBName)
 		}
 
 		lastInsertIDReturningSuffix := scope.Dialect().LastInsertIDReturningSuffix(quotedTableName, returningColumn)
+		lastInsertIDOutputInterstitial := scope.Dialect().LastInsertIDOutputInterstitial(quotedTableName, returningColumn, columns)
 
 		if len(columns) == 0 {
 			scope.Raw(fmt.Sprintf(
-				"INSERT INTO %v %v%v%v",
+				"INSERT%v INTO %v %v%v%v",
+				addExtraSpaceIfExist(insertModifier),
 				quotedTableName,
 				scope.Dialect().DefaultValueStr(),
 				addExtraSpaceIfExist(extraOption),
@@ -105,17 +114,19 @@ func createCallback(scope *Scope) {
 			))
 		} else {
 			scope.Raw(fmt.Sprintf(
-				"INSERT INTO %v (%v) VALUES (%v)%v%v",
+				"INSERT%v INTO %v (%v)%v VALUES (%v)%v%v",
+				addExtraSpaceIfExist(insertModifier),
 				scope.QuotedTableName(),
 				strings.Join(columns, ","),
+				addExtraSpaceIfExist(lastInsertIDOutputInterstitial),
 				strings.Join(placeholders, ","),
 				addExtraSpaceIfExist(extraOption),
 				addExtraSpaceIfExist(lastInsertIDReturningSuffix),
 			))
 		}
 
-		// execute create sql
+		// execute create sql: no primaryField
-		if lastInsertIDReturningSuffix == "" || primaryField == nil {
+		if primaryField == nil {
 			if result, err := scope.SQLDB().Exec(scope.SQL, scope.SQLVars...); scope.Err(err) == nil {
 				// set rows affected count
 				scope.db.RowsAffected, _ = result.RowsAffected()
@@ -127,16 +138,35 @@ func createCallback(scope *Scope) {
 					}
 				}
 			}
-		} else {
+			return
-			if primaryField.Field.CanAddr() {
-				if err := scope.SQLDB().QueryRow(scope.SQL, scope.SQLVars...).Scan(primaryField.Field.Addr().Interface()); scope.Err(err) == nil {
-					primaryField.IsBlank = false
-					scope.db.RowsAffected = 1
-				}
-			} else {
-				scope.Err(ErrUnaddressable)
-			}
 		}
+
+		// execute create sql: lastInsertID implemention for majority of dialects
+		if lastInsertIDReturningSuffix == "" && lastInsertIDOutputInterstitial == "" {
+			if result, err := scope.SQLDB().Exec(scope.SQL, scope.SQLVars...); scope.Err(err) == nil {
+				// set rows affected count
+				scope.db.RowsAffected, _ = result.RowsAffected()
+
+				// set primary value to primary field
+				if primaryField != nil && primaryField.IsBlank {
+					if primaryValue, err := result.LastInsertId(); scope.Err(err) == nil {
+						scope.Err(primaryField.Set(primaryValue))
+					}
+				}
+			}
+			return
+		}
+
+		// execute create sql: dialects with additional lastInsertID requirements (currently postgres & mssql)
+		if primaryField.Field.CanAddr() {
+			if err := scope.SQLDB().QueryRow(scope.SQL, scope.SQLVars...).Scan(primaryField.Field.Addr().Interface()); scope.Err(err) == nil {
+				primaryField.IsBlank = false
+				scope.db.RowsAffected = 1
+			}
+		} else {
+			scope.Err(ErrUnaddressable)
+		}
+		return
 	}
 }
 

callback_delete.go

@@ -17,7 +17,7 @@ func init() {
 // beforeDeleteCallback will invoke `BeforeDelete` method before deleting
 func beforeDeleteCallback(scope *Scope) {
 	if scope.DB().HasBlockGlobalUpdate() && !scope.hasConditions() {
-		scope.Err(errors.New("Missing WHERE clause while deleting"))
+		scope.Err(errors.New("missing WHERE clause while deleting"))
 		return
 	}
 	if !scope.HasError() {
@@ -40,7 +40,7 @@ func deleteCallback(scope *Scope) {
 				"UPDATE %v SET %v=%v%v%v",
 				scope.QuotedTableName(),
 				scope.Quote(deletedAtField.DBName),
-				scope.AddToVars(NowFunc()),
+				scope.AddToVars(scope.db.nowFunc()),
 				addExtraSpaceIfExist(scope.CombinedConditionSql()),
 				addExtraSpaceIfExist(extraOption),
 			)).Exec()

callback_query.go

@@ -19,7 +19,12 @@ func queryCallback(scope *Scope) {
 		return
 	}
 
-	defer scope.trace(NowFunc())
+	//we are only preloading relations, dont touch base model
+	if _, skip := scope.InstanceGet("gorm:only_preload"); skip {
+		return
+	}
+
+	defer scope.trace(scope.db.nowFunc())
 
 	var (
 		isSlice, isPtr bool

callback_query_preload.go

@@ -100,7 +100,7 @@ func autoPreload(scope *Scope) {
 			continue
 		}
 
-		if val, ok := field.TagSettings["PRELOAD"]; ok {
+		if val, ok := field.TagSettingsGet("PRELOAD"); ok {
 			if preload, err := strconv.ParseBool(val); err != nil {
 				scope.Err(errors.New("invalid preload option"))
 				return
@@ -161,14 +161,17 @@ func (scope *Scope) handleHasOnePreload(field *Field, conditions []interface{})
 	)
 
 	if indirectScopeValue.Kind() == reflect.Slice {
+		foreignValuesToResults := make(map[string]reflect.Value)
+		for i := 0; i < resultsValue.Len(); i++ {
+			result := resultsValue.Index(i)
+			foreignValues := toString(getValueFromFields(result, relation.ForeignFieldNames))
+			foreignValuesToResults[foreignValues] = result
+		}
 		for j := 0; j < indirectScopeValue.Len(); j++ {
-			for i := 0; i < resultsValue.Len(); i++ {
+			indirectValue := indirect(indirectScopeValue.Index(j))
-				result := resultsValue.Index(i)
+			valueString := toString(getValueFromFields(indirectValue, relation.AssociationForeignFieldNames))
-				foreignValues := getValueFromFields(result, relation.ForeignFieldNames)
+			if result, found := foreignValuesToResults[valueString]; found {
-				if indirectValue := indirect(indirectScopeValue.Index(j)); equalAsString(getValueFromFields(indirectValue, relation.AssociationForeignFieldNames), foreignValues) {
+				indirectValue.FieldByName(field.Name).Set(result)
-					indirectValue.FieldByName(field.Name).Set(result)
-					break
-				}
 			}
 		}
 	} else {
@@ -255,13 +258,21 @@ func (scope *Scope) handleBelongsToPreload(field *Field, conditions []interface{
 		indirectScopeValue = scope.IndirectValue()
 	)
 
+	foreignFieldToObjects := make(map[string][]*reflect.Value)
+	if indirectScopeValue.Kind() == reflect.Slice {
+		for j := 0; j < indirectScopeValue.Len(); j++ {
+			object := indirect(indirectScopeValue.Index(j))
+			valueString := toString(getValueFromFields(object, relation.ForeignFieldNames))
+			foreignFieldToObjects[valueString] = append(foreignFieldToObjects[valueString], &object)
+		}
+	}
+
 	for i := 0; i < resultsValue.Len(); i++ {
 		result := resultsValue.Index(i)
 		if indirectScopeValue.Kind() == reflect.Slice {
-			value := getValueFromFields(result, relation.AssociationForeignFieldNames)
+			valueString := toString(getValueFromFields(result, relation.AssociationForeignFieldNames))
-			for j := 0; j < indirectScopeValue.Len(); j++ {
+			if objects, found := foreignFieldToObjects[valueString]; found {
-				object := indirect(indirectScopeValue.Index(j))
+				for _, object := range objects {
-				if equalAsString(getValueFromFields(object, relation.ForeignFieldNames), value) {
 					object.FieldByName(field.Name).Set(result)
 				}
 			}
@@ -380,14 +391,20 @@ func (scope *Scope) handleManyToManyPreload(field *Field, conditions []interface
 		key := toString(getValueFromFields(indirectScopeValue, foreignFieldNames))
 		fieldsSourceMap[key] = append(fieldsSourceMap[key], indirectScopeValue.FieldByName(field.Name))
 	}
-	for source, link := range linkHash {
+
-		for i, field := range fieldsSourceMap[source] {
+	for source, fields := range fieldsSourceMap {
+		for _, f := range fields {
 			//If not 0 this means Value is a pointer and we already added preloaded models to it
-			if fieldsSourceMap[source][i].Len() != 0 {
+			if f.Len() != 0 {
 				continue
 			}
-			field.Set(reflect.Append(fieldsSourceMap[source][i], link...))
-		}
 
+			v := reflect.MakeSlice(f.Type(), 0, 0)
+			if len(linkHash[source]) > 0 {
+				v = reflect.Append(f, linkHash[source]...)
+			}
+
+			f.Set(v)
+		}
 	}
 }

callback_row_query.go

@@ -1,6 +1,9 @@
 package gorm
 
-import "database/sql"
+import (
+	"database/sql"
+	"fmt"
+)
 
 // Define callbacks for row query
 func init() {
@@ -20,6 +23,9 @@ type RowsQueryResult struct {
 func rowQueryCallback(scope *Scope) {
 	if result, ok := scope.InstanceGet("row_query_result"); ok {
 		scope.prepareQuerySQL()
+		if str, ok := scope.Get("gorm:query_option"); ok {
+			scope.SQL += addExtraSpaceIfExist(fmt.Sprint(str))
+		}
 
 		if rowResult, ok := result.(*RowQueryResult); ok {
 			rowResult.Row = scope.SQLDB().QueryRow(scope.SQL, scope.SQLVars...)

callback_save.go

@@ -21,9 +21,7 @@ func saveAssociationCheck(scope *Scope, field *Field) (autoUpdate bool, autoCrea
 
 		if v, ok := value.(string); ok {
 			v = strings.ToLower(v)
-			if v == "false" || v != "skip" {
+			return v == "true"
-				return false
-			}
 		}
 
 		return true
@@ -36,26 +34,28 @@ func saveAssociationCheck(scope *Scope, field *Field) (autoUpdate bool, autoCrea
 			if value, ok := scope.Get("gorm:save_associations"); ok {
 				autoUpdate = checkTruth(value)
 				autoCreate = autoUpdate
-			} else if value, ok := field.TagSettings["SAVE_ASSOCIATIONS"]; ok {
+				saveReference = autoUpdate
+			} else if value, ok := field.TagSettingsGet("SAVE_ASSOCIATIONS"); ok {
 				autoUpdate = checkTruth(value)
 				autoCreate = autoUpdate
+				saveReference = autoUpdate
 			}
 
 			if value, ok := scope.Get("gorm:association_autoupdate"); ok {
 				autoUpdate = checkTruth(value)
-			} else if value, ok := field.TagSettings["ASSOCIATION_AUTOUPDATE"]; ok {
+			} else if value, ok := field.TagSettingsGet("ASSOCIATION_AUTOUPDATE"); ok {
 				autoUpdate = checkTruth(value)
 			}
 
 			if value, ok := scope.Get("gorm:association_autocreate"); ok {
 				autoCreate = checkTruth(value)
-			} else if value, ok := field.TagSettings["ASSOCIATION_AUTOCREATE"]; ok {
+			} else if value, ok := field.TagSettingsGet("ASSOCIATION_AUTOCREATE"); ok {
 				autoCreate = checkTruth(value)
 			}
 
 			if value, ok := scope.Get("gorm:association_save_reference"); ok {
 				saveReference = checkTruth(value)
-			} else if value, ok := field.TagSettings["ASSOCIATION_SAVE_REFERENCE"]; ok {
+			} else if value, ok := field.TagSettingsGet("ASSOCIATION_SAVE_REFERENCE"); ok {
 				saveReference = checkTruth(value)
 			}
 		}

callback_system_test.go

@@ -23,7 +23,7 @@ func afterCreate1(s *Scope)  {}
 func afterCreate2(s *Scope)  {}
 
 func TestRegisterCallback(t *testing.T) {
-	var callback = &Callback{}
+	var callback = &Callback{logger: defaultLogger}
 
 	callback.Create().Register("before_create1", beforeCreate1)
 	callback.Create().Register("before_create2", beforeCreate2)
@@ -37,7 +37,7 @@ func TestRegisterCallback(t *testing.T) {
 }
 
 func TestRegisterCallbackWithOrder(t *testing.T) {
-	var callback1 = &Callback{}
+	var callback1 = &Callback{logger: defaultLogger}
 	callback1.Create().Register("before_create1", beforeCreate1)
 	callback1.Create().Register("create", create)
 	callback1.Create().Register("after_create1", afterCreate1)
@@ -46,7 +46,7 @@ func TestRegisterCallbackWithOrder(t *testing.T) {
 		t.Errorf("register callback with order")
 	}
 
-	var callback2 = &Callback{}
+	var callback2 = &Callback{logger: defaultLogger}
 
 	callback2.Update().Register("create", create)
 	callback2.Update().Before("create").Register("before_create1", beforeCreate1)
@@ -60,7 +60,7 @@ func TestRegisterCallbackWithOrder(t *testing.T) {
 }
 
 func TestRegisterCallbackWithComplexOrder(t *testing.T) {
-	var callback1 = &Callback{}
+	var callback1 = &Callback{logger: defaultLogger}
 
 	callback1.Query().Before("after_create1").After("before_create1").Register("create", create)
 	callback1.Query().Register("before_create1", beforeCreate1)
@@ -70,7 +70,7 @@ func TestRegisterCallbackWithComplexOrder(t *testing.T) {
 		t.Errorf("register callback with order")
 	}
 
-	var callback2 = &Callback{}
+	var callback2 = &Callback{logger: defaultLogger}
 
 	callback2.Delete().Before("after_create1").After("before_create1").Register("create", create)
 	callback2.Delete().Before("create").Register("before_create1", beforeCreate1)
@@ -86,7 +86,7 @@ func TestRegisterCallbackWithComplexOrder(t *testing.T) {
 func replaceCreate(s *Scope) {}
 
 func TestReplaceCallback(t *testing.T) {
-	var callback = &Callback{}
+	var callback = &Callback{logger: defaultLogger}
 
 	callback.Create().Before("after_create1").After("before_create1").Register("create", create)
 	callback.Create().Register("before_create1", beforeCreate1)
@@ -99,7 +99,7 @@ func TestReplaceCallback(t *testing.T) {
 }
 
 func TestRemoveCallback(t *testing.T) {
-	var callback = &Callback{}
+	var callback = &Callback{logger: defaultLogger}
 
 	callback.Create().Before("after_create1").After("before_create1").Register("create", create)
 	callback.Create().Register("before_create1", beforeCreate1)

callback_update.go

@@ -34,7 +34,7 @@ func assignUpdatingAttributesCallback(scope *Scope) {
 // beforeUpdateCallback will invoke `BeforeSave`, `BeforeUpdate` method before updating
 func beforeUpdateCallback(scope *Scope) {
 	if scope.DB().HasBlockGlobalUpdate() && !scope.hasConditions() {
-		scope.Err(errors.New("Missing WHERE clause while updating"))
+		scope.Err(errors.New("missing WHERE clause while updating"))
 		return
 	}
 	if _, ok := scope.Get("gorm:update_column"); !ok {
@@ -50,7 +50,7 @@ func beforeUpdateCallback(scope *Scope) {
 // updateTimeStampForUpdateCallback will set `UpdatedAt` when updating
 func updateTimeStampForUpdateCallback(scope *Scope) {
 	if _, ok := scope.Get("gorm:update_column"); !ok {
-		scope.SetColumn("UpdatedAt", NowFunc())
+		scope.SetColumn("UpdatedAt", scope.db.nowFunc())
 	}
 }
 
@@ -75,8 +75,10 @@ func updateCallback(scope *Scope) {
 		} else {
 			for _, field := range scope.Fields() {
 				if scope.changeableField(field) {
-					if !field.IsPrimaryKey && field.IsNormal {
+					if !field.IsPrimaryKey && field.IsNormal && (field.Name != "CreatedAt" || !field.IsBlank) {
-						sqls = append(sqls, fmt.Sprintf("%v = %v", scope.Quote(field.DBName), scope.AddToVars(field.Field.Interface())))
+						if !field.IsForeignKey || !field.IsBlank || !field.HasDefaultValue {
+							sqls = append(sqls, fmt.Sprintf("%v = %v", scope.Quote(field.DBName), scope.AddToVars(field.Field.Interface())))
+						}
 					} else if relationship := field.Relationship; relationship != nil && relationship.Kind == "belongs_to" {
 						for _, foreignKey := range relationship.ForeignDBNames {
 							if foreignField, ok := scope.FieldByName(foreignKey); ok && !scope.changeableField(foreignField) {

callbacks_test.go

@@ -2,11 +2,10 @@ package gorm_test
 
 import (
 	"errors"
-
-	"github.com/jinzhu/gorm"
-
 	"reflect"
 	"testing"
+
+	"github.com/jinzhu/gorm"
 )
 
 func (s *Product) BeforeCreate() (err error) {
@@ -175,3 +174,46 @@ func TestCallbacksWithErrors(t *testing.T) {
 		t.Errorf("Record shouldn't be deleted because of an error happened in after delete callback")
 	}
 }
+
+func TestGetCallback(t *testing.T) {
+	scope := DB.NewScope(nil)
+
+	if DB.Callback().Create().Get("gorm:test_callback") != nil {
+		t.Errorf("`gorm:test_callback` should be nil")
+	}
+
+	DB.Callback().Create().Register("gorm:test_callback", func(scope *gorm.Scope) { scope.Set("gorm:test_callback_value", 1) })
+	callback := DB.Callback().Create().Get("gorm:test_callback")
+	if callback == nil {
+		t.Errorf("`gorm:test_callback` should be non-nil")
+	}
+	callback(scope)
+	if v, ok := scope.Get("gorm:test_callback_value"); !ok || v != 1 {
+		t.Errorf("`gorm:test_callback_value` should be `1, true` but `%v, %v`", v, ok)
+	}
+
+	DB.Callback().Create().Replace("gorm:test_callback", func(scope *gorm.Scope) { scope.Set("gorm:test_callback_value", 2) })
+	callback = DB.Callback().Create().Get("gorm:test_callback")
+	if callback == nil {
+		t.Errorf("`gorm:test_callback` should be non-nil")
+	}
+	callback(scope)
+	if v, ok := scope.Get("gorm:test_callback_value"); !ok || v != 2 {
+		t.Errorf("`gorm:test_callback_value` should be `2, true` but `%v, %v`", v, ok)
+	}
+
+	DB.Callback().Create().Remove("gorm:test_callback")
+	if DB.Callback().Create().Get("gorm:test_callback") != nil {
+		t.Errorf("`gorm:test_callback` should be nil")
+	}
+
+	DB.Callback().Create().Register("gorm:test_callback", func(scope *gorm.Scope) { scope.Set("gorm:test_callback_value", 3) })
+	callback = DB.Callback().Create().Get("gorm:test_callback")
+	if callback == nil {
+		t.Errorf("`gorm:test_callback` should be non-nil")
+	}
+	callback(scope)
+	if v, ok := scope.Get("gorm:test_callback_value"); !ok || v != 3 {
+		t.Errorf("`gorm:test_callback_value` should be `3, true` but `%v, %v`", v, ok)
+	}
+}

create_test.go

@@ -101,6 +101,46 @@ func TestCreateWithExistingTimestamp(t *testing.T) {
 	}
 }
 
+func TestCreateWithNowFuncOverride(t *testing.T) {
+	user1 := User{Name: "CreateUserTimestampOverride"}
+
+	timeA := now.MustParse("2016-01-01")
+
+	// do DB.New() because we don't want this test to affect other tests
+	db1 := DB.New()
+	// set the override to use static timeA
+	db1.SetNowFuncOverride(func() time.Time {
+		return timeA
+	})
+	// call .New again to check the override is carried over as well during clone
+	db1 = db1.New()
+
+	db1.Save(&user1)
+
+	if user1.CreatedAt.UTC().Format(time.RFC3339) != timeA.UTC().Format(time.RFC3339) {
+		t.Errorf("CreatedAt be using the nowFuncOverride")
+	}
+	if user1.UpdatedAt.UTC().Format(time.RFC3339) != timeA.UTC().Format(time.RFC3339) {
+		t.Errorf("UpdatedAt be using the nowFuncOverride")
+	}
+
+	// now create another user with a fresh DB.Now() that doesn't have the nowFuncOverride set
+	// to make sure that setting it only affected the above instance
+
+	user2 := User{Name: "CreateUserTimestampOverrideNoMore"}
+
+	db2 := DB.New()
+
+	db2.Save(&user2)
+
+	if user2.CreatedAt.UTC().Format(time.RFC3339) == timeA.UTC().Format(time.RFC3339) {
+		t.Errorf("CreatedAt no longer be using the nowFuncOverride")
+	}
+	if user2.UpdatedAt.UTC().Format(time.RFC3339) == timeA.UTC().Format(time.RFC3339) {
+		t.Errorf("UpdatedAt no longer be using the nowFuncOverride")
+	}
+}
+
 type AutoIncrementUser struct {
 	User
 	Sequence uint `gorm:"AUTO_INCREMENT"`
@@ -229,3 +269,20 @@ func TestOmitWithCreate(t *testing.T) {
 		t.Errorf("Should not create omitted relationships")
 	}
 }
+
+func TestCreateIgnore(t *testing.T) {
+	float := 35.03554004971999
+	now := time.Now()
+	user := User{Name: "CreateUser", Age: 18, Birthday: &now, UserNum: Num(111), PasswordHash: []byte{'f', 'a', 'k', '4'}, Latitude: float}
+
+	if !DB.NewRecord(user) || !DB.NewRecord(&user) {
+		t.Error("User should be new record before create")
+	}
+
+	if count := DB.Create(&user).RowsAffected; count != 1 {
+		t.Error("There should be one record be affected when create record")
+	}
+	if DB.Dialect().GetName() == "mysql" && DB.Set("gorm:insert_modifier", "IGNORE").Create(&user).Error != nil {
+		t.Error("Should ignore duplicate user insert by insert modifier:IGNORE ")
+	}
+}

customize_column_test.go

@@ -289,6 +289,9 @@ type SelfReferencingUser struct {
 func TestSelfReferencingMany2ManyColumn(t *testing.T) {
 	DB.DropTable(&SelfReferencingUser{}, "UserFriends")
 	DB.AutoMigrate(&SelfReferencingUser{})
+	if !DB.HasTable("UserFriends") {
+		t.Errorf("auto migrate error, table UserFriends should be created")
+	}
 
 	friend1 := SelfReferencingUser{Name: "friend1_m2m"}
 	if err := DB.Create(&friend1).Error; err != nil {
@@ -313,6 +316,14 @@ func TestSelfReferencingMany2ManyColumn(t *testing.T) {
 		t.Errorf("Should find created friends correctly")
 	}
 
+	var count int
+	if err := DB.Table("UserFriends").Count(&count).Error; err != nil {
+		t.Errorf("no error should happen, but got %v", err)
+	}
+	if count == 0 {
+		t.Errorf("table UserFriends should have records")
+	}
+
 	var newUser = SelfReferencingUser{}
 
 	if err := DB.Preload("Friends").First(&newUser, "id = ?", user.ID).Error; err != nil {

dialect.go

@@ -40,6 +40,8 @@ type Dialect interface {
 	LimitAndOffsetSQL(limit, offset interface{}) string
 	// SelectFromDummyTable return select values, for most dbs, `SELECT values` just works, mysql needs `SELECT value FROM DUAL`
 	SelectFromDummyTable() string
+	// LastInsertIDOutputInterstitial most dbs support LastInsertId, but mssql needs to use `OUTPUT`
+	LastInsertIDOutputInterstitial(tableName, columnName string, columns []string) string
 	// LastInsertIdReturningSuffix most dbs support LastInsertId, but postgres needs to use `RETURNING`
 	LastInsertIDReturningSuffix(tableName, columnName string) string
 	// DefaultValueStr
@@ -48,6 +50,9 @@ type Dialect interface {
 	// BuildKeyName returns a valid key name (foreign key, index key) for the given table, field and reference
 	BuildKeyName(kind, tableName string, fields ...string) string
 
+	// NormalizeIndexAndColumn returns valid index name and column name depending on each dialect
+	NormalizeIndexAndColumn(indexName, columnName string) (string, string)
+
 	// CurrentDatabase return current database name
 	CurrentDatabase() string
 }
@@ -83,7 +88,7 @@ var ParseFieldStructForDialect = func(field *StructField, dialect Dialect) (fiel
 	// Get redirected field type
 	var (
 		reflectType = field.Struct.Type
-		dataType    = field.TagSettings["TYPE"]
+		dataType, _ = field.TagSettingsGet("TYPE")
 	)
 
 	for reflectType.Kind() == reflect.Ptr {
@@ -112,18 +117,24 @@ var ParseFieldStructForDialect = func(field *StructField, dialect Dialect) (fiel
 	}
 
 	// Default Size
-	if num, ok := field.TagSettings["SIZE"]; ok {
+	if num, ok := field.TagSettingsGet("SIZE"); ok {
 		size, _ = strconv.Atoi(num)
 	} else {
 		size = 255
 	}
 
 	// Default type from tag setting
-	additionalType = field.TagSettings["NOT NULL"] + " " + field.TagSettings["UNIQUE"]
+	notNull, _ := field.TagSettingsGet("NOT NULL")
-	if value, ok := field.TagSettings["DEFAULT"]; ok {
+	unique, _ := field.TagSettingsGet("UNIQUE")
+	additionalType = notNull + " " + unique
+	if value, ok := field.TagSettingsGet("DEFAULT"); ok {
 		additionalType = additionalType + " DEFAULT " + value
 	}
 
+	if value, ok := field.TagSettingsGet("COMMENT"); ok {
+		additionalType = additionalType + " COMMENT " + value
+	}
+
 	return fieldValue, dataType, size, strings.TrimSpace(additionalType)
 }
 

dialect_common.go

@@ -9,6 +9,8 @@ import (
 	"time"
 )
 
+var keyNameRegex = regexp.MustCompile("[^a-zA-Z0-9]+")
+
 // DefaultForeignKeyNamer contains the default foreign key name generator method
 type DefaultForeignKeyNamer struct {
 }
@@ -39,7 +41,7 @@ func (commonDialect) Quote(key string) string {
 }
 
 func (s *commonDialect) fieldCanAutoIncrement(field *StructField) bool {
-	if value, ok := field.TagSettings["AUTO_INCREMENT"]; ok {
+	if value, ok := field.TagSettingsGet("AUTO_INCREMENT"); ok {
 		return strings.ToLower(value) != "false"
 	}
 	return field.IsPrimaryKey
@@ -155,6 +157,10 @@ func (commonDialect) SelectFromDummyTable() string {
 	return ""
 }
 
+func (commonDialect) LastInsertIDOutputInterstitial(tableName, columnName string, columns []string) string {
+	return ""
+}
+
 func (commonDialect) LastInsertIDReturningSuffix(tableName, columnName string) string {
 	return ""
 }
@@ -166,10 +172,15 @@ func (commonDialect) DefaultValueStr() string {
 // BuildKeyName returns a valid key name (foreign key, index key) for the given table, field and reference
 func (DefaultForeignKeyNamer) BuildKeyName(kind, tableName string, fields ...string) string {
 	keyName := fmt.Sprintf("%s_%s_%s", kind, tableName, strings.Join(fields, "_"))
-	keyName = regexp.MustCompile("[^a-zA-Z0-9]+").ReplaceAllString(keyName, "_")
+	keyName = keyNameRegex.ReplaceAllString(keyName, "_")
 	return keyName
 }
 
+// NormalizeIndexAndColumn returns argument's index name and column name without doing anything
+func (commonDialect) NormalizeIndexAndColumn(indexName, columnName string) (string, string) {
+	return indexName, columnName
+}
+
 // IsByteArrayOrSlice returns true of the reflected value is an array or slice
 func IsByteArrayOrSlice(value reflect.Value) bool {
 	return (value.Kind() == reflect.Array || value.Kind() == reflect.Slice) && value.Type().Elem() == reflect.TypeOf(uint8(0))

dialect_mysql.go

@@ -11,6 +11,8 @@ import (
 	"unicode/utf8"
 )
 
+var mysqlIndexRegex = regexp.MustCompile(`^(.+)\((\d+)\)$`)
+
 type mysql struct {
 	commonDialect
 }
@@ -33,9 +35,9 @@ func (s *mysql) DataTypeOf(field *StructField) string {
 
 	// MySQL allows only one auto increment column per table, and it must
 	// be a KEY column.
-	if _, ok := field.TagSettings["AUTO_INCREMENT"]; ok {
+	if _, ok := field.TagSettingsGet("AUTO_INCREMENT"); ok {
-		if _, ok = field.TagSettings["INDEX"]; !ok && !field.IsPrimaryKey {
+		if _, ok = field.TagSettingsGet("INDEX"); !ok && !field.IsPrimaryKey {
-			delete(field.TagSettings, "AUTO_INCREMENT")
+			field.TagSettingsDelete("AUTO_INCREMENT")
 		}
 	}
 
@@ -45,42 +47,42 @@ func (s *mysql) DataTypeOf(field *StructField) string {
 			sqlType = "boolean"
 		case reflect.Int8:
 			if s.fieldCanAutoIncrement(field) {
-				field.TagSettings["AUTO_INCREMENT"] = "AUTO_INCREMENT"
+				field.TagSettingsSet("AUTO_INCREMENT", "AUTO_INCREMENT")
 				sqlType = "tinyint AUTO_INCREMENT"
 			} else {
 				sqlType = "tinyint"
 			}
 		case reflect.Int, reflect.Int16, reflect.Int32:
 			if s.fieldCanAutoIncrement(field) {
-				field.TagSettings["AUTO_INCREMENT"] = "AUTO_INCREMENT"
+				field.TagSettingsSet("AUTO_INCREMENT", "AUTO_INCREMENT")
 				sqlType = "int AUTO_INCREMENT"
 			} else {
 				sqlType = "int"
 			}
 		case reflect.Uint8:
 			if s.fieldCanAutoIncrement(field) {
-				field.TagSettings["AUTO_INCREMENT"] = "AUTO_INCREMENT"
+				field.TagSettingsSet("AUTO_INCREMENT", "AUTO_INCREMENT")
 				sqlType = "tinyint unsigned AUTO_INCREMENT"
 			} else {
 				sqlType = "tinyint unsigned"
 			}
 		case reflect.Uint, reflect.Uint16, reflect.Uint32, reflect.Uintptr:
 			if s.fieldCanAutoIncrement(field) {
-				field.TagSettings["AUTO_INCREMENT"] = "AUTO_INCREMENT"
+				field.TagSettingsSet("AUTO_INCREMENT", "AUTO_INCREMENT")
 				sqlType = "int unsigned AUTO_INCREMENT"
 			} else {
 				sqlType = "int unsigned"
 			}
 		case reflect.Int64:
 			if s.fieldCanAutoIncrement(field) {
-				field.TagSettings["AUTO_INCREMENT"] = "AUTO_INCREMENT"
+				field.TagSettingsSet("AUTO_INCREMENT", "AUTO_INCREMENT")
 				sqlType = "bigint AUTO_INCREMENT"
 			} else {
 				sqlType = "bigint"
 			}
 		case reflect.Uint64:
 			if s.fieldCanAutoIncrement(field) {
-				field.TagSettings["AUTO_INCREMENT"] = "AUTO_INCREMENT"
+				field.TagSettingsSet("AUTO_INCREMENT", "AUTO_INCREMENT")
 				sqlType = "bigint unsigned AUTO_INCREMENT"
 			} else {
 				sqlType = "bigint unsigned"
@@ -96,11 +98,11 @@ func (s *mysql) DataTypeOf(field *StructField) string {
 		case reflect.Struct:
 			if _, ok := dataValue.Interface().(time.Time); ok {
 				precision := ""
-				if p, ok := field.TagSettings["PRECISION"]; ok {
+				if p, ok := field.TagSettingsGet("PRECISION"); ok {
 					precision = fmt.Sprintf("(%s)", p)
 				}
 
-				if _, ok := field.TagSettings["NOT NULL"]; ok {
+				if _, ok := field.TagSettings["NOT NULL"]; ok || field.IsPrimaryKey {
 					sqlType = fmt.Sprintf("DATETIME%v", precision)
 				} else {
 					sqlType = fmt.Sprintf("DATETIME%v NULL", precision)
@@ -118,7 +120,7 @@ func (s *mysql) DataTypeOf(field *StructField) string {
 	}
 
 	if sqlType == "" {
-		panic(fmt.Sprintf("invalid sql type %s (%s) for mysql", dataValue.Type().Name(), dataValue.Kind().String()))
+		panic(fmt.Sprintf("invalid sql type %s (%s) in field %s for mysql", dataValue.Type().Name(), dataValue.Kind().String(), field.Name))
 	}
 
 	if strings.TrimSpace(additionalType) == "" {
@@ -178,7 +180,7 @@ func (s mysql) BuildKeyName(kind, tableName string, fields ...string) string {
 	bs := h.Sum(nil)
 
 	// sha1 is 40 characters, keep first 24 characters of destination
-	destRunes := []rune(regexp.MustCompile("[^a-zA-Z0-9]+").ReplaceAllString(fields[0], "_"))
+	destRunes := []rune(keyNameRegex.ReplaceAllString(fields[0], "_"))
 	if len(destRunes) > 24 {
 		destRunes = destRunes[:24]
 	}
@@ -186,6 +188,17 @@ func (s mysql) BuildKeyName(kind, tableName string, fields ...string) string {
 	return fmt.Sprintf("%s%x", string(destRunes), bs)
 }
 
+// NormalizeIndexAndColumn returns index name and column name for specify an index prefix length if needed
+func (mysql) NormalizeIndexAndColumn(indexName, columnName string) (string, string) {
+	submatch := mysqlIndexRegex.FindStringSubmatch(indexName)
+	if len(submatch) != 3 {
+		return indexName, columnName
+	}
+	indexName = submatch[1]
+	columnName = fmt.Sprintf("%s(%s)", columnName, submatch[2])
+	return indexName, columnName
+}
+
 func (mysql) DefaultValueStr() string {
 	return "VALUES()"
 }

dialect_postgres.go

@@ -34,14 +34,14 @@ func (s *postgres) DataTypeOf(field *StructField) string {
 			sqlType = "boolean"
 		case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uintptr:
 			if s.fieldCanAutoIncrement(field) {
-				field.TagSettings["AUTO_INCREMENT"] = "AUTO_INCREMENT"
+				field.TagSettingsSet("AUTO_INCREMENT", "AUTO_INCREMENT")
 				sqlType = "serial"
 			} else {
 				sqlType = "integer"
 			}
 		case reflect.Int64, reflect.Uint32, reflect.Uint64:
 			if s.fieldCanAutoIncrement(field) {
-				field.TagSettings["AUTO_INCREMENT"] = "AUTO_INCREMENT"
+				field.TagSettingsSet("AUTO_INCREMENT", "AUTO_INCREMENT")
 				sqlType = "bigserial"
 			} else {
 				sqlType = "bigint"
@@ -49,7 +49,7 @@ func (s *postgres) DataTypeOf(field *StructField) string {
 		case reflect.Float32, reflect.Float64:
 			sqlType = "numeric"
 		case reflect.String:
-			if _, ok := field.TagSettings["SIZE"]; !ok {
+			if _, ok := field.TagSettingsGet("SIZE"); !ok {
 				size = 0 // if SIZE haven't been set, use `text` as the default type, as there are no performance different
 			}
 
@@ -120,6 +120,10 @@ func (s postgres) CurrentDatabase() (name string) {
 	return
 }
 
+func (s postgres) LastInsertIDOutputInterstitial(tableName, key string, columns []string) string {
+	return ""
+}
+
 func (s postgres) LastInsertIDReturningSuffix(tableName, key string) string {
 	return fmt.Sprintf("RETURNING %v.%v", tableName, key)
 }

dialect_sqlite3.go

@@ -29,14 +29,14 @@ func (s *sqlite3) DataTypeOf(field *StructField) string {
 			sqlType = "bool"
 		case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uintptr:
 			if s.fieldCanAutoIncrement(field) {
-				field.TagSettings["AUTO_INCREMENT"] = "AUTO_INCREMENT"
+				field.TagSettingsSet("AUTO_INCREMENT", "AUTO_INCREMENT")
 				sqlType = "integer primary key autoincrement"
 			} else {
 				sqlType = "integer"
 			}
 		case reflect.Int64, reflect.Uint64:
 			if s.fieldCanAutoIncrement(field) {
-				field.TagSettings["AUTO_INCREMENT"] = "AUTO_INCREMENT"
+				field.TagSettingsSet("AUTO_INCREMENT", "AUTO_INCREMENT")
 				sqlType = "integer primary key autoincrement"
 			} else {
 				sqlType = "bigint"

dialects/mssql/mssql.go

@@ -18,7 +18,7 @@ import (
 func setIdentityInsert(scope *gorm.Scope) {
 	if scope.Dialect().GetName() == "mssql" {
 		for _, field := range scope.PrimaryFields() {
-			if _, ok := field.TagSettings["AUTO_INCREMENT"]; ok && !field.IsBlank {
+			if _, ok := field.TagSettingsGet("AUTO_INCREMENT"); ok && !field.IsBlank {
 				scope.NewDB().Exec(fmt.Sprintf("SET IDENTITY_INSERT %v ON", scope.TableName()))
 				scope.InstanceSet("mssql:identity_insert_on", true)
 			}
@@ -70,14 +70,14 @@ func (s *mssql) DataTypeOf(field *gorm.StructField) string {
 			sqlType = "bit"
 		case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uintptr:
 			if s.fieldCanAutoIncrement(field) {
-				field.TagSettings["AUTO_INCREMENT"] = "AUTO_INCREMENT"
+				field.TagSettingsSet("AUTO_INCREMENT", "AUTO_INCREMENT")
 				sqlType = "int IDENTITY(1,1)"
 			} else {
 				sqlType = "int"
 			}
 		case reflect.Int64, reflect.Uint64:
 			if s.fieldCanAutoIncrement(field) {
-				field.TagSettings["AUTO_INCREMENT"] = "AUTO_INCREMENT"
+				field.TagSettingsSet("AUTO_INCREMENT", "AUTO_INCREMENT")
 				sqlType = "bigint IDENTITY(1,1)"
 			} else {
 				sqlType = "bigint"
@@ -116,7 +116,7 @@ func (s *mssql) DataTypeOf(field *gorm.StructField) string {
 }
 
 func (s mssql) fieldCanAutoIncrement(field *gorm.StructField) bool {
-	if value, ok := field.TagSettings["AUTO_INCREMENT"]; ok {
+	if value, ok := field.TagSettingsGet("AUTO_INCREMENT"); ok {
 		return value != "FALSE"
 	}
 	return field.IsPrimaryKey
@@ -190,6 +190,14 @@ func (mssql) SelectFromDummyTable() string {
 	return ""
 }
 
+func (mssql) LastInsertIDOutputInterstitial(tableName, columnName string, columns []string) string {
+	if len(columns) == 0 {
+		// No OUTPUT to query
+		return ""
+	}
+	return fmt.Sprintf("OUTPUT Inserted.%v", columnName)
+}
+
 func (mssql) LastInsertIDReturningSuffix(tableName, columnName string) string {
 	return ""
 }
@@ -198,6 +206,11 @@ func (mssql) DefaultValueStr() string {
 	return "DEFAULT VALUES"
 }
 
+// NormalizeIndexAndColumn returns argument's index name and column name without doing anything
+func (mssql) NormalizeIndexAndColumn(indexName, columnName string) (string, string) {
+	return indexName, columnName
+}
+
 func currentDatabaseAndTable(dialect gorm.Dialect, tableName string) (string, string) {
 	if strings.Contains(tableName, ".") {
 		splitStrings := strings.SplitN(tableName, ".", 2)

dialects/postgres/postgres.go

@@ -7,6 +7,7 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+
 	_ "github.com/lib/pq"
 	"github.com/lib/pq/hstore"
 )

errors.go

@@ -6,11 +6,11 @@ import (
 )
 
 var (
-	// ErrRecordNotFound record not found error, happens when only haven't find any matched data when looking up with a struct, finding a slice won't return this error
+	// ErrRecordNotFound returns a "record not found error". Occurs only when attempting to query the database with a struct; querying with a slice won't return this error
 	ErrRecordNotFound = errors.New("record not found")
-	// ErrInvalidSQL invalid SQL error, happens when you passed invalid SQL
+	// ErrInvalidSQL occurs when you attempt a query with invalid SQL
 	ErrInvalidSQL = errors.New("invalid SQL")
-	// ErrInvalidTransaction invalid transaction when you are trying to `Commit` or `Rollback`
+	// ErrInvalidTransaction occurs when you are trying to `Commit` or `Rollback`
 	ErrInvalidTransaction = errors.New("no valid transaction")
 	// ErrCantStartTransaction can't start transaction when you are trying to start one with `Begin`
 	ErrCantStartTransaction = errors.New("can't start transaction")
@@ -21,7 +21,7 @@ var (
 // Errors contains all happened errors
 type Errors []error
 
-// IsRecordNotFoundError returns current error has record not found error or not
+// IsRecordNotFoundError returns true if error contains a RecordNotFound error
 func IsRecordNotFoundError(err error) bool {
 	if errs, ok := err.(Errors); ok {
 		for _, err := range errs {
@@ -33,12 +33,12 @@ func IsRecordNotFoundError(err error) bool {
 	return err == ErrRecordNotFound
 }
 
-// GetErrors gets all happened errors
+// GetErrors gets all errors that have occurred and returns a slice of errors (Error type)
 func (errs Errors) GetErrors() []error {
 	return errs
 }
 
-// Add adds an error
+// Add adds an error to a given slice of errors
 func (errs Errors) Add(newErrors ...error) Errors {
 	for _, err := range newErrors {
 		if err == nil {
@@ -62,7 +62,7 @@ func (errs Errors) Add(newErrors ...error) Errors {
 	return errs
 }
 
-// Error format happened errors
+// Error takes a slice of all errors that have occurred and returns it as a formatted string
 func (errs Errors) Error() string {
 	var errors = []string{}
 	for _, e := range errs {

field.go

@@ -2,6 +2,7 @@ package gorm
 
 import (
 	"database/sql"
+	"database/sql/driver"
 	"errors"
 	"fmt"
 	"reflect"
@@ -44,7 +45,14 @@ func (field *Field) Set(value interface{}) (err error) {
 			if reflectValue.Type().ConvertibleTo(fieldValue.Type()) {
 				fieldValue.Set(reflectValue.Convert(fieldValue.Type()))
 			} else if scanner, ok := fieldValue.Addr().Interface().(sql.Scanner); ok {
-				err = scanner.Scan(reflectValue.Interface())
+				v := reflectValue.Interface()
+				if valuer, ok := v.(driver.Valuer); ok {
+					if v, err = valuer.Value(); err == nil {
+						err = scanner.Scan(v)
+					}
+				} else {
+					err = scanner.Scan(v)
+				}
 			} else {
 				err = fmt.Errorf("could not convert argument of field %s from %s to %s", field.Name, reflectValue.Type(), fieldValue.Type())
 			}

field_test.go

@@ -1,6 +1,9 @@
 package gorm_test
 
 import (
+	"database/sql/driver"
+	"encoding/hex"
+	"fmt"
 	"testing"
 
 	"github.com/jinzhu/gorm"
@@ -43,7 +46,85 @@ func TestCalculateField(t *testing.T) {
 
 	if field, ok := scope.FieldByName("embedded_name"); !ok {
 		t.Errorf("should find embedded field")
-	} else if _, ok := field.TagSettings["NOT NULL"]; !ok {
+	} else if _, ok := field.TagSettingsGet("NOT NULL"); !ok {
 		t.Errorf("should find embedded field's tag settings")
 	}
 }
+
+type UUID [16]byte
+
+type NullUUID struct {
+	UUID
+	Valid bool
+}
+
+func FromString(input string) (u UUID) {
+	src := []byte(input)
+	return FromBytes(src)
+}
+
+func FromBytes(src []byte) (u UUID) {
+	dst := u[:]
+	hex.Decode(dst[0:4], src[0:8])
+	hex.Decode(dst[4:6], src[9:13])
+	hex.Decode(dst[6:8], src[14:18])
+	hex.Decode(dst[8:10], src[19:23])
+	hex.Decode(dst[10:], src[24:])
+	return
+}
+
+func (u UUID) String() string {
+	buf := make([]byte, 36)
+	src := u[:]
+	hex.Encode(buf[0:8], src[0:4])
+	buf[8] = '-'
+	hex.Encode(buf[9:13], src[4:6])
+	buf[13] = '-'
+	hex.Encode(buf[14:18], src[6:8])
+	buf[18] = '-'
+	hex.Encode(buf[19:23], src[8:10])
+	buf[23] = '-'
+	hex.Encode(buf[24:], src[10:])
+	return string(buf)
+}
+
+func (u UUID) Value() (driver.Value, error) {
+	return u.String(), nil
+}
+
+func (u *UUID) Scan(src interface{}) error {
+	switch src := src.(type) {
+	case UUID: // support gorm convert from UUID to NullUUID
+		*u = src
+		return nil
+	case []byte:
+		*u = FromBytes(src)
+		return nil
+	case string:
+		*u = FromString(src)
+		return nil
+	}
+	return fmt.Errorf("uuid: cannot convert %T to UUID", src)
+}
+
+func (u *NullUUID) Scan(src interface{}) error {
+	u.Valid = true
+	return u.UUID.Scan(src)
+}
+
+func TestFieldSet(t *testing.T) {
+	type TestFieldSetNullUUID struct {
+		NullUUID NullUUID
+	}
+	scope := DB.NewScope(&TestFieldSetNullUUID{})
+	field := scope.Fields()[0]
+	err := field.Set(FromString("3034d44a-da03-11e8-b366-4a00070b9f00"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if id, ok := field.Field.Addr().Interface().(*NullUUID); !ok {
+		t.Fatal()
+	} else if !id.Valid || id.UUID.String() != "3034d44a-da03-11e8-b366-4a00070b9f00" {
+		t.Fatal(id)
+	}
+}

go.mod

@@ -0,0 +1,13 @@
+module github.com/jinzhu/gorm
+
+go 1.12
+
+require (
+	github.com/denisenkom/go-mssqldb v0.0.0-20190515213511-eb9f6a1743f3
+	github.com/erikstmartin/go-testdb v0.0.0-20160219214506-8d10e4a1bae5
+	github.com/go-sql-driver/mysql v1.4.1
+	github.com/jinzhu/inflection v1.0.0
+	github.com/jinzhu/now v1.0.1
+	github.com/lib/pq v1.1.1
+	github.com/mattn/go-sqlite3 v1.11.0
+)

go.sum

@@ -0,0 +1,131 @@
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+github.com/Shopify/sarama v1.19.0/go.mod h1:FVkBWblsNy7DGZRfXLU0O9RCGt5g3g3yEuWXgklEdEo=
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+golang.org/x/net v0.0.0-20190108225652-1e06a53dbb7e/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
+golang.org/x/net v0.0.0-20190125091013-d26f9f9a57f3/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
+golang.org/x/net v0.0.0-20190213061140-3a22650c66bd/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
+golang.org/x/net v0.0.0-20190311183353-d8887717615a/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
+golang.org/x/oauth2 v0.0.0-20190226205417-e64efc72b421/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
+golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.0.0-20181108010431-42b317875d0f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.0.0-20181221193216-37e7f081c4d4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.0.0-20190227155943-e225da77a7e6/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sys v0.0.0-20180830151530-49385e6e1522/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20180905080454-ebe1bf3edb33/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20180909124046-d0be0721c37e/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20181116152217-5ac8a444bdc5/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20181122145206-62eef0e2fa9b/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+golang.org/x/text v0.3.1-0.20180807135948-17ff2d5776d2/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+golang.org/x/time v0.0.0-20181108054448-85acf8d2951c/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
+golang.org/x/tools v0.0.0-20180828015842-6cd1fcedba52/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
+golang.org/x/tools v0.0.0-20190114222345-bf090417da8b/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
+golang.org/x/tools v0.0.0-20190226205152-f727befe758c/go.mod h1:9Yl7xja0Znq3iFh3HoIrodX9oNMXvdceNzlUR8zjMvY=
+golang.org/x/tools v0.0.0-20190312170243-e65039ee4138/go.mod h1:LCzVGOaR6xXOjkQ3onu1FJEFr0SW1gC7cKk1uF8kGRs=
+google.golang.org/api v0.3.1/go.mod h1:6wY9I6uQWHQ8EM57III9mq/AjF+i8G65rmVagqKMtkk=
+google.golang.org/appengine v1.1.0/go.mod h1:EbEs0AVv82hx2wNQdGPgUI5lhzA/G0D9YwlJXL52JkM=
+google.golang.org/appengine v1.4.0 h1:/wp5JvzpHIxhs/dumFmF7BXTf3Z+dd4uXta4kVyO508=
+google.golang.org/appengine v1.4.0/go.mod h1:xpcJRLb0r/rnEns0DIKYYv+WjYCduHsrkT7/EB5XEv4=
+google.golang.org/genproto v0.0.0-20180817151627-c66870c02cf8/go.mod h1:JiN7NxoALGmiZfu7CAH4rXhgtRTLTxftemlI0sWmxmc=
+google.golang.org/genproto v0.0.0-20190307195333-5fe7a883aa19/go.mod h1:VzzqZJRnGkLBvHegQrXjBqPurQTc5/KpmUdxsrq26oE=
+google.golang.org/genproto v0.0.0-20190404172233-64821d5d2107/go.mod h1:VzzqZJRnGkLBvHegQrXjBqPurQTc5/KpmUdxsrq26oE=
+google.golang.org/grpc v1.17.0/go.mod h1:6QZJwpn2B+Zp71q/5VxRsJ6NXXVCE5NRUHRo+f3cWCs=
+google.golang.org/grpc v1.19.0/go.mod h1:mqu4LbDTu4XGKhr4mRzUsmM4RtVoemTSY81AxZiDr8c=
+gopkg.in/alecthomas/kingpin.v2 v2.2.6/go.mod h1:FMv+mEhP44yOT+4EoQTLFTRgOQ1FBLkstjWtayDeSgw=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/fsnotify.v1 v1.4.7/go.mod h1:Tz8NjZHkW78fSQdbUxIjBTcgA1z1m8ZHf0WmKUhAMys=
+gopkg.in/tomb.v1 v1.0.0-20141024135613-dd632973f1e7/go.mod h1:dt/ZhP58zS4L8KSrWDmTeBkI65Dw0HsyUHuEVlX15mw=
+gopkg.in/yaml.v2 v2.2.1/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
+gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
+honnef.co/go/tools v0.0.0-20180728063816-88497007e858/go.mod h1:rf3lG4BRIbNafJWhAfAdb/ePZxsR/4RtNHQocxwk9r4=
+honnef.co/go/tools v0.0.0-20190102054323-c2f93a96b099/go.mod h1:rf3lG4BRIbNafJWhAfAdb/ePZxsR/4RtNHQocxwk9r4=
+honnef.co/go/tools v0.0.0-20190106161140-3f1c8253044a/go.mod h1:rf3lG4BRIbNafJWhAfAdb/ePZxsR/4RtNHQocxwk9r4=

interface.go

@@ -1,6 +1,9 @@
 package gorm
 
-import "database/sql"
+import (
+	"context"
+	"database/sql"
+)
 
 // SQLCommon is the minimal database connection functionality gorm requires.  Implemented by *sql.DB.
 type SQLCommon interface {
@@ -12,6 +15,7 @@ type SQLCommon interface {
 
 type sqlDb interface {
 	Begin() (*sql.Tx, error)
+	BeginTx(ctx context.Context, opts *sql.TxOptions) (*sql.Tx, error)
 }
 
 type sqlTx interface {

logger.go

@@ -49,7 +49,11 @@ var LogFormatter = func(values ...interface{}) (messages []interface{}) {
 				if indirectValue.IsValid() {
 					value = indirectValue.Interface()
 					if t, ok := value.(time.Time); ok {
-						formattedValues = append(formattedValues, fmt.Sprintf("'%v'", t.Format("2006-01-02 15:04:05")))
+						if t.IsZero() {
+							formattedValues = append(formattedValues, fmt.Sprintf("'%v'", "0000-00-00 00:00:00"))
+						} else {
+							formattedValues = append(formattedValues, fmt.Sprintf("'%v'", t.Format("2006-01-02 15:04:05")))
+						}
 					} else if b, ok := value.([]byte); ok {
 						if str := string(b); isPrintable(str) {
 							formattedValues = append(formattedValues, fmt.Sprintf("'%v'", str))
@@ -63,7 +67,12 @@ var LogFormatter = func(values ...interface{}) (messages []interface{}) {
 							formattedValues = append(formattedValues, "NULL")
 						}
 					} else {
-						formattedValues = append(formattedValues, fmt.Sprintf("'%v'", value))
+						switch value.(type) {
+						case int, int8, int16, int32, int64, uint, uint8, uint16, uint32, uint64, float32, float64, bool:
+							formattedValues = append(formattedValues, fmt.Sprintf("%v", value))
+						default:
+							formattedValues = append(formattedValues, fmt.Sprintf("'%v'", value))
+						}
 					}
 				} else {
 					formattedValues = append(formattedValues, "NULL")

main.go

@@ -1,6 +1,7 @@
 package gorm
 
 import (
+	"context"
 	"database/sql"
 	"errors"
 	"fmt"
@@ -12,6 +13,7 @@ import (
 
 // DB contains information for current db connection
 type DB struct {
+	sync.RWMutex
 	Value        interface{}
 	Error        error
 	RowsAffected int64
@@ -19,18 +21,29 @@ type DB struct {
 	// single db
 	db                SQLCommon
 	blockGlobalUpdate bool
-	logMode           int
+	logMode           logModeValue
 	logger            logger
 	search            *search
-	values            map[string]interface{}
+	values            sync.Map
 
 	// global db
 	parent        *DB
 	callbacks     *Callback
 	dialect       Dialect
 	singularTable bool
+
+	// function to be used to override the creating of a new timestamp
+	nowFuncOverride func() time.Time
 }
 
+type logModeValue int
+
+const (
+	defaultLogMode logModeValue = iota
+	noLogMode
+	detailedLogMode
+)
+
 // Open initialize a new db connection, need to import driver first, e.g:
 //
 //     import _ "github.com/go-sql-driver/mysql"
@@ -72,7 +85,6 @@ func Open(dialect string, args ...interface{}) (db *DB, err error) {
 	db = &DB{
 		db:        dbSQL,
 		logger:    defaultLogger,
-		values:    map[string]interface{}{},
 		callbacks: DefaultCallback,
 		dialect:   newDialect(dialect, dbSQL),
 	}
@@ -130,7 +142,7 @@ func (s *DB) Dialect() Dialect {
 //     db.Callback().Create().Register("update_created_at", updateCreated)
 // Refer https://jinzhu.github.io/gorm/development.html#callbacks
 func (s *DB) Callback() *Callback {
-	s.parent.callbacks = s.parent.callbacks.clone()
+	s.parent.callbacks = s.parent.callbacks.clone(s.logger)
 	return s.parent.callbacks
 }
 
@@ -142,13 +154,29 @@ func (s *DB) SetLogger(log logger) {
 // LogMode set log mode, `true` for detailed logs, `false` for no log, default, will only print error logs
 func (s *DB) LogMode(enable bool) *DB {
 	if enable {
-		s.logMode = 2
+		s.logMode = detailedLogMode
 	} else {
-		s.logMode = 1
+		s.logMode = noLogMode
 	}
 	return s
 }
 
+// SetNowFuncOverride set the function to be used when creating a new timestamp
+func (s *DB) SetNowFuncOverride(nowFuncOverride func() time.Time) *DB {
+	s.nowFuncOverride = nowFuncOverride
+	return s
+}
+
+// Get a new timestamp, using the provided nowFuncOverride on the DB instance if set,
+// otherwise defaults to the global NowFunc()
+func (s *DB) nowFunc() time.Time {
+	if s.nowFuncOverride != nil {
+		return s.nowFuncOverride()
+	}
+
+	return NowFunc()
+}
+
 // BlockGlobalUpdate if true, generates an error on update/delete without where clause.
 // This is to prevent eventual error with empty objects updates/deletions
 func (s *DB) BlockGlobalUpdate(enable bool) *DB {
@@ -163,7 +191,8 @@ func (s *DB) HasBlockGlobalUpdate() bool {
 
 // SingularTable use singular table by default
 func (s *DB) SingularTable(enable bool) {
-	modelStructsMap = sync.Map{}
+	s.parent.Lock()
+	defer s.parent.Unlock()
 	s.parent.singularTable = enable
 }
 
@@ -171,7 +200,13 @@ func (s *DB) SingularTable(enable bool) {
 func (s *DB) NewScope(value interface{}) *Scope {
 	dbClone := s.clone()
 	dbClone.Value = value
-	return &Scope{db: dbClone, Search: dbClone.search.clone(), Value: value}
+	scope := &Scope{db: dbClone, Value: value}
+	if s.search != nil {
+		scope.Search = s.search.clone()
+	} else {
+		scope.Search = &search{}
+	}
+	return scope
 }
 
 // QueryExpr returns the query as expr object
@@ -291,6 +326,7 @@ func (s *DB) Assign(attrs ...interface{}) *DB {
 func (s *DB) First(out interface{}, where ...interface{}) *DB {
 	newScope := s.NewScope(out)
 	newScope.Search.Limit(1)
+
 	return newScope.Set("gorm:order_by_primary_key", "ASC").
 		inlineCondition(where...).callCallbacks(s.parent.callbacks.queries).db
 }
@@ -315,6 +351,11 @@ func (s *DB) Find(out interface{}, where ...interface{}) *DB {
 	return s.NewScope(out).inlineCondition(where...).callCallbacks(s.parent.callbacks.queries).db
 }
 
+//Preloads preloads relations, don`t touch out
+func (s *DB) Preloads(out interface{}) *DB {
+	return s.NewScope(out).InstanceSet("gorm:only_preload", 1).callCallbacks(s.parent.callbacks.queries).db
+}
+
 // Scan scan value to a struct
 func (s *DB) Scan(dest interface{}) *DB {
 	return s.NewScope(s.Value).Set("gorm:query_destination", dest).callCallbacks(s.parent.callbacks.queries).db
@@ -425,7 +466,7 @@ func (s *DB) Save(value interface{}) *DB {
 	if !scope.PrimaryKeyZero() {
 		newDB := scope.callCallbacks(s.parent.callbacks.updates).db
 		if newDB.Error == nil && newDB.RowsAffected == 0 {
-			return s.New().FirstOrCreate(value)
+			return s.New().Table(scope.TableName()).FirstOrCreate(value)
 		}
 		return newDB
 	}
@@ -482,11 +523,16 @@ func (s *DB) Debug() *DB {
 	return s.clone().LogMode(true)
 }
 
-// Begin begin a transaction
+// Begin begins a transaction
 func (s *DB) Begin() *DB {
+	return s.BeginTx(context.Background(), &sql.TxOptions{})
+}
+
+// BeginTx begins a transaction with options
+func (s *DB) BeginTx(ctx context.Context, opts *sql.TxOptions) *DB {
 	c := s.clone()
 	if db, ok := c.db.(sqlDb); ok && db != nil {
-		tx, err := db.Begin()
+		tx, err := db.BeginTx(ctx, opts)
 		c.db = interface{}(tx).(SQLCommon)
 
 		c.dialect.SetDB(c.db)
@@ -512,7 +558,26 @@ func (s *DB) Commit() *DB {
 func (s *DB) Rollback() *DB {
 	var emptySQLTx *sql.Tx
 	if db, ok := s.db.(sqlTx); ok && db != nil && db != emptySQLTx {
-		s.AddError(db.Rollback())
+		if err := db.Rollback(); err != nil && err != sql.ErrTxDone {
+			s.AddError(err)
+		}
+	} else {
+		s.AddError(ErrInvalidTransaction)
+	}
+	return s
+}
+
+// RollbackUnlessCommitted rollback a transaction if it has not yet been
+// committed.
+func (s *DB) RollbackUnlessCommitted() *DB {
+	var emptySQLTx *sql.Tx
+	if db, ok := s.db.(sqlTx); ok && db != nil && db != emptySQLTx {
+		err := db.Rollback()
+		// Ignore the error indicating that the transaction has already
+		// been committed.
+		if err != sql.ErrTxDone {
+			s.AddError(err)
+		}
 	} else {
 		s.AddError(ErrInvalidTransaction)
 	}
@@ -680,13 +745,13 @@ func (s *DB) Set(name string, value interface{}) *DB {
 
 // InstantSet instant set setting, will affect current db
 func (s *DB) InstantSet(name string, value interface{}) *DB {
-	s.values[name] = value
+	s.values.Store(name, value)
 	return s
 }
 
 // Get get setting by name
 func (s *DB) Get(name string) (value interface{}, ok bool) {
-	value, ok = s.values[name]
+	value, ok = s.values.Load(name)
 	return
 }
 
@@ -695,7 +760,7 @@ func (s *DB) SetJoinTableHandler(source interface{}, column string, handler Join
 	scope := s.NewScope(source)
 	for _, field := range scope.GetModelStruct().StructFields {
 		if field.Name == column || field.DBName == column {
-			if many2many := field.TagSettings["MANY2MANY"]; many2many != "" {
+			if many2many, _ := field.TagSettingsGet("MANY2MANY"); many2many != "" {
 				source := (&Scope{Value: source}).GetModelStruct().ModelType
 				destination := (&Scope{Value: reflect.New(field.Struct.Type).Interface()}).GetModelStruct().ModelType
 				handler.Setup(field.Relationship, many2many, source, destination)
@@ -712,8 +777,8 @@ func (s *DB) SetJoinTableHandler(source interface{}, column string, handler Join
 func (s *DB) AddError(err error) error {
 	if err != nil {
 		if err != ErrRecordNotFound {
-			if s.logMode == 0 {
+			if s.logMode == defaultLogMode {
-				go s.print(fileWithLineNum(), err)
+				go s.print("error", fileWithLineNum(), err)
 			} else {
 				s.log(err)
 			}
@@ -750,16 +815,17 @@ func (s *DB) clone() *DB {
 		parent:            s.parent,
 		logger:            s.logger,
 		logMode:           s.logMode,
-		values:            map[string]interface{}{},
 		Value:             s.Value,
 		Error:             s.Error,
 		blockGlobalUpdate: s.blockGlobalUpdate,
 		dialect:           newDialect(s.dialect.GetName(), s.db),
+		nowFuncOverride:   s.nowFuncOverride,
 	}
 
-	for key, value := range s.values {
+	s.values.Range(func(k, v interface{}) bool {
-		db.values[key] = value
+		db.values.Store(k, v)
-	}
+		return true
+	})
 
 	if s.search == nil {
 		db.search = &search{limit: -1, offset: -1}
@@ -776,13 +842,13 @@ func (s *DB) print(v ...interface{}) {
 }
 
 func (s *DB) log(v ...interface{}) {
-	if s != nil && s.logMode == 2 {
+	if s != nil && s.logMode == detailedLogMode {
 		s.print(append([]interface{}{"log", fileWithLineNum()}, v...)...)
 	}
 }
 
 func (s *DB) slog(sql string, t time.Time, vars ...interface{}) {
-	if s.logMode == 2 {
+	if s.logMode == detailedLogMode {
 		s.print("sql", fileWithLineNum(), NowFunc().Sub(t), sql, vars, s.RowsAffected)
 	}
 }

main_test.go

@@ -1,6 +1,11 @@
 package gorm_test
 
+// Run tests
+// $ docker-compose up
+// $ ./test_all.sh
+
 import (
+	"context"
 	"database/sql"
 	"database/sql/driver"
 	"fmt"
@@ -9,6 +14,7 @@ import (
 	"reflect"
 	"strconv"
 	"strings"
+	"sync"
 	"testing"
 	"time"
 
@@ -176,6 +182,15 @@ func TestSetTable(t *testing.T) {
 		t.Errorf("Query from specified table")
 	}
 
+	var user User
+	DB.Table("deleted_users").First(&user, "name = ?", "DeletedUser")
+
+	user.Age = 20
+	DB.Table("deleted_users").Save(&user)
+	if DB.Table("deleted_users").First(&user, "name = ? AND age = ?", "DeletedUser", 20).RecordNotFound() {
+		t.Errorf("Failed to found updated user")
+	}
+
 	DB.Save(getPreparedUser("normal_user", "reset_table"))
 	DB.Table("deleted_users").Save(getPreparedUser("deleted_user", "reset_table"))
 	var user1, user2, user3 User
@@ -277,6 +292,30 @@ func TestTableName(t *testing.T) {
 	DB.SingularTable(false)
 }
 
+func TestTableNameConcurrently(t *testing.T) {
+	DB := DB.Model("")
+	if DB.NewScope(Order{}).TableName() != "orders" {
+		t.Errorf("Order's table name should be orders")
+	}
+
+	var wg sync.WaitGroup
+	wg.Add(10)
+
+	for i := 1; i <= 10; i++ {
+		go func(db *gorm.DB) {
+			DB.SingularTable(true)
+			wg.Done()
+		}(DB)
+	}
+	wg.Wait()
+
+	if DB.NewScope(Order{}).TableName() != "order" {
+		t.Errorf("Order's singular table name should be order")
+	}
+
+	DB.SingularTable(false)
+}
+
 func TestNullValues(t *testing.T) {
 	DB.DropTable(&NullValue{})
 	DB.AutoMigrate(&NullValue{})
@@ -394,6 +433,90 @@ func TestTransaction(t *testing.T) {
 	if err := DB.First(&User{}, "name = ?", "transcation-2").Error; err != nil {
 		t.Errorf("Should be able to find committed record")
 	}
+
+	tx3 := DB.Begin()
+	u3 := User{Name: "transcation-3"}
+	if err := tx3.Save(&u3).Error; err != nil {
+		t.Errorf("No error should raise")
+	}
+
+	if err := tx3.First(&User{}, "name = ?", "transcation-3").Error; err != nil {
+		t.Errorf("Should find saved record")
+	}
+
+	tx3.RollbackUnlessCommitted()
+
+	if err := tx.First(&User{}, "name = ?", "transcation").Error; err == nil {
+		t.Errorf("Should not find record after rollback")
+	}
+
+	tx4 := DB.Begin()
+	u4 := User{Name: "transcation-4"}
+	if err := tx4.Save(&u4).Error; err != nil {
+		t.Errorf("No error should raise")
+	}
+
+	if err := tx4.First(&User{}, "name = ?", "transcation-4").Error; err != nil {
+		t.Errorf("Should find saved record")
+	}
+
+	tx4.Commit()
+
+	tx4.RollbackUnlessCommitted()
+
+	if err := DB.First(&User{}, "name = ?", "transcation-4").Error; err != nil {
+		t.Errorf("Should be able to find committed record")
+	}
+}
+
+func TestTransaction_NoErrorOnRollbackAfterCommit(t *testing.T) {
+	tx := DB.Begin()
+	u := User{Name: "transcation"}
+	if err := tx.Save(&u).Error; err != nil {
+		t.Errorf("No error should raise")
+	}
+
+	if err := tx.Commit().Error; err != nil {
+		t.Errorf("Commit should not raise error")
+	}
+
+	if err := tx.Rollback().Error; err != nil {
+		t.Errorf("Rollback should not raise error")
+	}
+}
+
+func TestTransactionReadonly(t *testing.T) {
+	dialect := os.Getenv("GORM_DIALECT")
+	if dialect == "" {
+		dialect = "sqlite"
+	}
+	switch dialect {
+	case "mssql", "sqlite":
+		t.Skipf("%s does not support readonly transactions\n", dialect)
+	}
+
+	tx := DB.Begin()
+	u := User{Name: "transcation"}
+	if err := tx.Save(&u).Error; err != nil {
+		t.Errorf("No error should raise")
+	}
+	tx.Commit()
+
+	tx = DB.BeginTx(context.Background(), &sql.TxOptions{ReadOnly: true})
+	if err := tx.First(&User{}, "name = ?", "transcation").Error; err != nil {
+		t.Errorf("Should find saved record")
+	}
+
+	if sqlTx, ok := tx.CommonDB().(*sql.Tx); !ok || sqlTx == nil {
+		t.Errorf("Should return the underlying sql.Tx")
+	}
+
+	u = User{Name: "transcation-2"}
+	if err := tx.Save(&u).Error; err == nil {
+		t.Errorf("Error should have been raised in a readonly transaction")
+	}
+
+	tx.Rollback()
 }
 
 func TestRow(t *testing.T) {
@@ -581,6 +704,60 @@ func TestJoins(t *testing.T) {
 	}
 }
 
+type JoinedIds struct {
+	UserID           int64 `gorm:"column:id"`
+	BillingAddressID int64 `gorm:"column:id"`
+	EmailID          int64 `gorm:"column:id"`
+}
+
+func TestScanIdenticalColumnNames(t *testing.T) {
+	var user = User{
+		Name:  "joinsIds",
+		Email: "joinIds@example.com",
+		BillingAddress: Address{
+			Address1: "One Park Place",
+		},
+		Emails: []Email{{Email: "join1@example.com"}, {Email: "join2@example.com"}},
+	}
+	DB.Save(&user)
+
+	var users []JoinedIds
+	DB.Select("users.id, addresses.id, emails.id").Table("users").
+		Joins("left join addresses on users.billing_address_id = addresses.id").
+		Joins("left join emails on emails.user_id = users.id").
+		Where("name = ?", "joinsIds").Scan(&users)
+
+	if len(users) != 2 {
+		t.Fatal("should find two rows using left join")
+	}
+
+	if user.Id != users[0].UserID {
+		t.Errorf("Expected result row to contain UserID %d, but got %d", user.Id, users[0].UserID)
+	}
+	if user.Id != users[1].UserID {
+		t.Errorf("Expected result row to contain UserID %d, but got %d", user.Id, users[1].UserID)
+	}
+
+	if user.BillingAddressID.Int64 != users[0].BillingAddressID {
+		t.Errorf("Expected result row to contain BillingAddressID %d, but got %d", user.BillingAddressID.Int64, users[0].BillingAddressID)
+	}
+	if user.BillingAddressID.Int64 != users[1].BillingAddressID {
+		t.Errorf("Expected result row to contain BillingAddressID %d, but got %d", user.BillingAddressID.Int64, users[0].BillingAddressID)
+	}
+
+	if users[0].EmailID == users[1].EmailID {
+		t.Errorf("Email ids should be unique. Got %d and %d", users[0].EmailID, users[1].EmailID)
+	}
+
+	if int64(user.Emails[0].Id) != users[0].EmailID && int64(user.Emails[1].Id) != users[0].EmailID {
+		t.Errorf("Expected result row ID to be either %d or %d, but was %d", user.Emails[0].Id, user.Emails[1].Id, users[0].EmailID)
+	}
+
+	if int64(user.Emails[0].Id) != users[1].EmailID && int64(user.Emails[1].Id) != users[1].EmailID {
+		t.Errorf("Expected result row ID to be either %d or %d, but was %d", user.Emails[0].Id, user.Emails[1].Id, users[1].EmailID)
+	}
+}
+
 func TestJoinsWithSelect(t *testing.T) {
 	type result struct {
 		Name  string
@@ -879,6 +1056,94 @@ func TestOpenWithOneParameter(t *testing.T) {
 	}
 }
 
+func TestSaveAssociations(t *testing.T) {
+	db := DB.New()
+	deltaAddressCount := 0
+	if err := db.Model(&Address{}).Count(&deltaAddressCount).Error; err != nil {
+		t.Errorf("failed to fetch address count")
+		t.FailNow()
+	}
+
+	placeAddress := &Address{
+		Address1: "somewhere on earth",
+	}
+	ownerAddress1 := &Address{
+		Address1: "near place address",
+	}
+	ownerAddress2 := &Address{
+		Address1: "address2",
+	}
+	db.Create(placeAddress)
+
+	addressCountShouldBe := func(t *testing.T, expectedCount int) {
+		countFromDB := 0
+		t.Helper()
+		err := db.Model(&Address{}).Count(&countFromDB).Error
+		if err != nil {
+			t.Error("failed to fetch address count")
+		}
+		if countFromDB != expectedCount {
+			t.Errorf("address count mismatch: %d", countFromDB)
+		}
+	}
+	addressCountShouldBe(t, deltaAddressCount+1)
+
+	// owner address should be created, place address should be reused
+	place1 := &Place{
+		PlaceAddressID: placeAddress.ID,
+		PlaceAddress:   placeAddress,
+		OwnerAddress:   ownerAddress1,
+	}
+	err := db.Create(place1).Error
+	if err != nil {
+		t.Errorf("failed to store place: %s", err.Error())
+	}
+	addressCountShouldBe(t, deltaAddressCount+2)
+
+	// owner address should be created again, place address should be reused
+	place2 := &Place{
+		PlaceAddressID: placeAddress.ID,
+		PlaceAddress: &Address{
+			ID:       777,
+			Address1: "address1",
+		},
+		OwnerAddress:   ownerAddress2,
+		OwnerAddressID: 778,
+	}
+	err = db.Create(place2).Error
+	if err != nil {
+		t.Errorf("failed to store place: %s", err.Error())
+	}
+	addressCountShouldBe(t, deltaAddressCount+3)
+
+	count := 0
+	db.Model(&Place{}).Where(&Place{
+		PlaceAddressID: placeAddress.ID,
+		OwnerAddressID: ownerAddress1.ID,
+	}).Count(&count)
+	if count != 1 {
+		t.Errorf("only one instance of (%d, %d) should be available, found: %d",
+			placeAddress.ID, ownerAddress1.ID, count)
+	}
+
+	db.Model(&Place{}).Where(&Place{
+		PlaceAddressID: placeAddress.ID,
+		OwnerAddressID: ownerAddress2.ID,
+	}).Count(&count)
+	if count != 1 {
+		t.Errorf("only one instance of (%d, %d) should be available, found: %d",
+			placeAddress.ID, ownerAddress2.ID, count)
+	}
+
+	db.Model(&Place{}).Where(&Place{
+		PlaceAddressID: placeAddress.ID,
+	}).Count(&count)
+	if count != 2 {
+		t.Errorf("two instances of (%d) should be available, found: %d",
+			placeAddress.ID, count)
+	}
+}
+
 func TestBlockGlobalUpdate(t *testing.T) {
 	db := DB.New()
 	db.Create(&Toy{Name: "Stuffed Animal", OwnerType: "Nobody"})
@@ -917,6 +1182,124 @@ func TestBlockGlobalUpdate(t *testing.T) {
 	}
 }
 
+func TestCountWithHaving(t *testing.T) {
+	db := DB.New()
+	db.Delete(User{})
+	defer db.Delete(User{})
+
+	DB.Create(getPreparedUser("user1", "pluck_user"))
+	DB.Create(getPreparedUser("user2", "pluck_user"))
+	user3 := getPreparedUser("user3", "pluck_user")
+	user3.Languages = []Language{}
+	DB.Create(user3)
+
+	var count int
+	err := db.Model(User{}).Select("users.id").
+		Joins("LEFT JOIN user_languages ON user_languages.user_id = users.id").
+		Joins("LEFT JOIN languages ON user_languages.language_id = languages.id").
+		Group("users.id").Having("COUNT(languages.id) > 1").Count(&count).Error
+
+	if err != nil {
+		t.Error("Unexpected error on query count with having")
+	}
+
+	if count != 2 {
+		t.Error("Unexpected result on query count with having")
+	}
+}
+
+func TestPluck(t *testing.T) {
+	db := DB.New()
+	db.Delete(User{})
+	defer db.Delete(User{})
+
+	DB.Create(&User{Id: 1, Name: "user1"})
+	DB.Create(&User{Id: 2, Name: "user2"})
+	DB.Create(&User{Id: 3, Name: "user3"})
+
+	var ids []int64
+	err := db.Model(User{}).Order("id").Pluck("id", &ids).Error
+
+	if err != nil {
+		t.Error("Unexpected error on pluck")
+	}
+
+	if len(ids) != 3 || ids[0] != 1 || ids[1] != 2 || ids[2] != 3 {
+		t.Error("Unexpected result on pluck")
+	}
+
+	err = db.Model(User{}).Order("id").Pluck("id", &ids).Error
+
+	if err != nil {
+		t.Error("Unexpected error on pluck again")
+	}
+
+	if len(ids) != 3 || ids[0] != 1 || ids[1] != 2 || ids[2] != 3 {
+		t.Error("Unexpected result on pluck again")
+	}
+}
+
+func TestCountWithQueryOption(t *testing.T) {
+	db := DB.New()
+	db.Delete(User{})
+	defer db.Delete(User{})
+
+	DB.Create(&User{Name: "user1"})
+	DB.Create(&User{Name: "user2"})
+	DB.Create(&User{Name: "user3"})
+
+	var count int
+	err := db.Model(User{}).Select("users.id").
+		Set("gorm:query_option", "WHERE users.name='user2'").
+		Count(&count).Error
+
+	if err != nil {
+		t.Error("Unexpected error on query count with query_option")
+	}
+
+	if count != 1 {
+		t.Error("Unexpected result on query count with query_option")
+	}
+}
+
+func TestFloatColumnPrecision(t *testing.T) {
+	if dialect := os.Getenv("GORM_DIALECT"); dialect != "mysql" && dialect != "sqlite" {
+		t.Skip()
+	}
+
+	type FloatTest struct {
+		ID         string  `gorm:"primary_key"`
+		FloatValue float64 `gorm:"column:float_value" sql:"type:float(255,5);"`
+	}
+	DB.DropTable(&FloatTest{})
+	DB.AutoMigrate(&FloatTest{})
+
+	data := FloatTest{ID: "uuid", FloatValue: 112.57315}
+	if err := DB.Save(&data).Error; err != nil || data.ID != "uuid" || data.FloatValue != 112.57315 {
+		t.Errorf("Float value should not lose precision")
+	}
+}
+
+func TestWhereUpdates(t *testing.T) {
+	type OwnerEntity struct {
+		gorm.Model
+		OwnerID   uint
+		OwnerType string
+	}
+
+	type SomeEntity struct {
+		gorm.Model
+		Name        string
+		OwnerEntity OwnerEntity `gorm:"polymorphic:Owner"`
+	}
+
+	DB.DropTable(&SomeEntity{})
+	DB.AutoMigrate(&SomeEntity{})
+
+	a := SomeEntity{Name: "test"}
+	DB.Model(&a).Where(a).Updates(SomeEntity{Name: "test2"})
+}
+
 func BenchmarkGorm(b *testing.B) {
 	b.N = 2000
 	for x := 0; x < b.N; x++ {

migration_test.go

@@ -118,6 +118,14 @@ type Company struct {
 	Owner *User `sql:"-"`
 }
 
+type Place struct {
+	Id             int64
+	PlaceAddressID int
+	PlaceAddress   *Address `gorm:"save_associations:false"`
+	OwnerAddressID int
+	OwnerAddress   *Address `gorm:"save_associations:true"`
+}
+
 type EncryptedData []byte
 
 func (data *EncryptedData) Scan(value interface{}) error {
@@ -284,7 +292,7 @@ func runMigration() {
 		DB.Exec(fmt.Sprintf("drop table %v;", table))
 	}
 
-	values := []interface{}{&Short{}, &ReallyLongThingThatReferencesShort{}, &ReallyLongTableNameToTestMySQLNameLengthLimit{}, &NotSoLongTableName{}, &Product{}, &Email{}, &Address{}, &CreditCard{}, &Company{}, &Role{}, &Language{}, &HNPost{}, &EngadgetPost{}, &Animal{}, &User{}, &JoinTable{}, &Post{}, &Category{}, &Comment{}, &Cat{}, &Dog{}, &Hamster{}, &Toy{}, &ElementWithIgnoredField{}}
+	values := []interface{}{&Short{}, &ReallyLongThingThatReferencesShort{}, &ReallyLongTableNameToTestMySQLNameLengthLimit{}, &NotSoLongTableName{}, &Product{}, &Email{}, &Address{}, &CreditCard{}, &Company{}, &Role{}, &Language{}, &HNPost{}, &EngadgetPost{}, &Animal{}, &User{}, &JoinTable{}, &Post{}, &Category{}, &Comment{}, &Cat{}, &Dog{}, &Hamster{}, &Toy{}, &ElementWithIgnoredField{}, &Place{}}
 	for _, value := range values {
 		DB.DropTable(value)
 	}
@@ -530,3 +538,42 @@ func TestModifyColumnType(t *testing.T) {
 		t.Errorf("No error should happen when ModifyColumn, but got %v", err)
 	}
 }
+
+func TestIndexWithPrefixLength(t *testing.T) {
+	if dialect := os.Getenv("GORM_DIALECT"); dialect != "mysql" {
+		t.Skip("Skipping this because only mysql support setting an index prefix length")
+	}
+
+	type IndexWithPrefix struct {
+		gorm.Model
+		Name        string
+		Description string `gorm:"type:text;index:idx_index_with_prefixes_length(100)"`
+	}
+	type IndexesWithPrefix struct {
+		gorm.Model
+		Name         string
+		Description1 string `gorm:"type:text;index:idx_index_with_prefixes_length(100)"`
+		Description2 string `gorm:"type:text;index:idx_index_with_prefixes_length(100)"`
+	}
+	type IndexesWithPrefixAndWithoutPrefix struct {
+		gorm.Model
+		Name        string `gorm:"index:idx_index_with_prefixes_length"`
+		Description string `gorm:"type:text;index:idx_index_with_prefixes_length(100)"`
+	}
+	tables := []interface{}{&IndexWithPrefix{}, &IndexesWithPrefix{}, &IndexesWithPrefixAndWithoutPrefix{}}
+	for _, table := range tables {
+		scope := DB.NewScope(table)
+		tableName := scope.TableName()
+		t.Run(fmt.Sprintf("Create index with prefix length: %s", tableName), func(t *testing.T) {
+			if err := DB.DropTableIfExists(table).Error; err != nil {
+				t.Errorf("Failed to drop %s table: %v", tableName, err)
+			}
+			if err := DB.CreateTable(table).Error; err != nil {
+				t.Errorf("Failed to create %s table: %v", tableName, err)
+			}
+			if !scope.Dialect().HasIndex(tableName, "idx_index_with_prefixes_length") {
+				t.Errorf("Failed to create %s table index:", tableName)
+			}
+		})
+	}
+}

model_struct.go

@@ -21,23 +21,30 @@ var modelStructsMap sync.Map
 
 // ModelStruct model definition
 type ModelStruct struct {
-	PrimaryFields    []*StructField
+	PrimaryFields []*StructField
-	StructFields     []*StructField
+	StructFields  []*StructField
-	ModelType        reflect.Type
+	ModelType     reflect.Type
+
 	defaultTableName string
+	l                sync.Mutex
 }
 
 // TableName returns model's table name
 func (s *ModelStruct) TableName(db *DB) string {
+	s.l.Lock()
+	defer s.l.Unlock()
+
 	if s.defaultTableName == "" && db != nil && s.ModelType != nil {
 		// Set default table name
 		if tabler, ok := reflect.New(s.ModelType).Interface().(tabler); ok {
 			s.defaultTableName = tabler.TableName()
 		} else {
-			tableName := ToDBName(s.ModelType.Name())
+			tableName := ToTableName(s.ModelType.Name())
-			if db == nil || !db.parent.singularTable {
+			db.parent.RLock()
+			if db == nil || (db.parent != nil && !db.parent.singularTable) {
 				tableName = inflection.Plural(tableName)
 			}
+			db.parent.RUnlock()
 			s.defaultTableName = tableName
 		}
 	}
@@ -60,30 +67,57 @@ type StructField struct {
 	Struct          reflect.StructField
 	IsForeignKey    bool
 	Relationship    *Relationship
+
+	tagSettingsLock sync.RWMutex
 }
 
-func (structField *StructField) clone() *StructField {
+// TagSettingsSet Sets a tag in the tag settings map
+func (sf *StructField) TagSettingsSet(key, val string) {
+	sf.tagSettingsLock.Lock()
+	defer sf.tagSettingsLock.Unlock()
+	sf.TagSettings[key] = val
+}
+
+// TagSettingsGet returns a tag from the tag settings
+func (sf *StructField) TagSettingsGet(key string) (string, bool) {
+	sf.tagSettingsLock.RLock()
+	defer sf.tagSettingsLock.RUnlock()
+	val, ok := sf.TagSettings[key]
+	return val, ok
+}
+
+// TagSettingsDelete deletes a tag
+func (sf *StructField) TagSettingsDelete(key string) {
+	sf.tagSettingsLock.Lock()
+	defer sf.tagSettingsLock.Unlock()
+	delete(sf.TagSettings, key)
+}
+
+func (sf *StructField) clone() *StructField {
 	clone := &StructField{
-		DBName:          structField.DBName,
+		DBName:          sf.DBName,
-		Name:            structField.Name,
+		Name:            sf.Name,
-		Names:           structField.Names,
+		Names:           sf.Names,
-		IsPrimaryKey:    structField.IsPrimaryKey,
+		IsPrimaryKey:    sf.IsPrimaryKey,
-		IsNormal:        structField.IsNormal,
+		IsNormal:        sf.IsNormal,
-		IsIgnored:       structField.IsIgnored,
+		IsIgnored:       sf.IsIgnored,
-		IsScanner:       structField.IsScanner,
+		IsScanner:       sf.IsScanner,
-		HasDefaultValue: structField.HasDefaultValue,
+		HasDefaultValue: sf.HasDefaultValue,
-		Tag:             structField.Tag,
+		Tag:             sf.Tag,
 		TagSettings:     map[string]string{},
-		Struct:          structField.Struct,
+		Struct:          sf.Struct,
-		IsForeignKey:    structField.IsForeignKey,
+		IsForeignKey:    sf.IsForeignKey,
 	}
 
-	if structField.Relationship != nil {
+	if sf.Relationship != nil {
-		relationship := *structField.Relationship
+		relationship := *sf.Relationship
 		clone.Relationship = &relationship
 	}
 
-	for key, value := range structField.TagSettings {
+	// copy the struct field tagSettings, they should be read-locked while they are copied
+	sf.tagSettingsLock.Lock()
+	defer sf.tagSettingsLock.Unlock()
+	for key, value := range sf.TagSettings {
 		clone.TagSettings[key] = value
 	}
 
@@ -105,7 +139,7 @@ type Relationship struct {
 
 func getForeignField(column string, fields []*StructField) *StructField {
 	for _, field := range fields {
-		if field.Name == column || field.DBName == column || field.DBName == ToDBName(column) {
+		if field.Name == column || field.DBName == column || field.DBName == ToColumnName(column) {
 			return field
 		}
 	}
@@ -131,7 +165,18 @@ func (scope *Scope) GetModelStruct() *ModelStruct {
 	}
 
 	// Get Cached model struct
-	if value, ok := modelStructsMap.Load(reflectType); ok && value != nil {
+	isSingularTable := false
+	if scope.db != nil && scope.db.parent != nil {
+		scope.db.parent.RLock()
+		isSingularTable = scope.db.parent.singularTable
+		scope.db.parent.RUnlock()
+	}
+
+	hashKey := struct {
+		singularTable bool
+		reflectType   reflect.Type
+	}{isSingularTable, reflectType}
+	if value, ok := modelStructsMap.Load(hashKey); ok && value != nil {
 		return value.(*ModelStruct)
 	}
 
@@ -149,19 +194,19 @@ func (scope *Scope) GetModelStruct() *ModelStruct {
 			}
 
 			// is ignored field
-			if _, ok := field.TagSettings["-"]; ok {
+			if _, ok := field.TagSettingsGet("-"); ok {
 				field.IsIgnored = true
 			} else {
-				if _, ok := field.TagSettings["PRIMARY_KEY"]; ok {
+				if _, ok := field.TagSettingsGet("PRIMARY_KEY"); ok {
 					field.IsPrimaryKey = true
 					modelStruct.PrimaryFields = append(modelStruct.PrimaryFields, field)
 				}
 
-				if _, ok := field.TagSettings["DEFAULT"]; ok {
+				if _, ok := field.TagSettingsGet("DEFAULT"); ok && !field.IsPrimaryKey {
 					field.HasDefaultValue = true
 				}
 
-				if _, ok := field.TagSettings["AUTO_INCREMENT"]; ok && !field.IsPrimaryKey {
+				if _, ok := field.TagSettingsGet("AUTO_INCREMENT"); ok && !field.IsPrimaryKey {
 					field.HasDefaultValue = true
 				}
 
@@ -177,8 +222,8 @@ func (scope *Scope) GetModelStruct() *ModelStruct {
 					if indirectType.Kind() == reflect.Struct {
 						for i := 0; i < indirectType.NumField(); i++ {
 							for key, value := range parseTagSetting(indirectType.Field(i).Tag) {
-								if _, ok := field.TagSettings[key]; !ok {
+								if _, ok := field.TagSettingsGet(key); !ok {
-									field.TagSettings[key] = value
+									field.TagSettingsSet(key, value)
 								}
 							}
 						}
@@ -186,17 +231,17 @@ func (scope *Scope) GetModelStruct() *ModelStruct {
 				} else if _, isTime := fieldValue.(*time.Time); isTime {
 					// is time
 					field.IsNormal = true
-				} else if _, ok := field.TagSettings["EMBEDDED"]; ok || fieldStruct.Anonymous {
+				} else if _, ok := field.TagSettingsGet("EMBEDDED"); ok || fieldStruct.Anonymous {
 					// is embedded struct
 					for _, subField := range scope.New(fieldValue).GetModelStruct().StructFields {
 						subField = subField.clone()
 						subField.Names = append([]string{fieldStruct.Name}, subField.Names...)
-						if prefix, ok := field.TagSettings["EMBEDDED_PREFIX"]; ok {
+						if prefix, ok := field.TagSettingsGet("EMBEDDED_PREFIX"); ok {
 							subField.DBName = prefix + subField.DBName
 						}
 
 						if subField.IsPrimaryKey {
-							if _, ok := subField.TagSettings["PRIMARY_KEY"]; ok {
+							if _, ok := subField.TagSettingsGet("PRIMARY_KEY"); ok {
 								modelStruct.PrimaryFields = append(modelStruct.PrimaryFields, subField)
 							} else {
 								subField.IsPrimaryKey = false
@@ -227,13 +272,13 @@ func (scope *Scope) GetModelStruct() *ModelStruct {
 								elemType               = field.Struct.Type
 							)
 
-							if foreignKey := field.TagSettings["FOREIGNKEY"]; foreignKey != "" {
+							if foreignKey, _ := field.TagSettingsGet("FOREIGNKEY"); foreignKey != "" {
 								foreignKeys = strings.Split(foreignKey, ",")
 							}
 
-							if foreignKey := field.TagSettings["ASSOCIATION_FOREIGNKEY"]; foreignKey != "" {
+							if foreignKey, _ := field.TagSettingsGet("ASSOCIATION_FOREIGNKEY"); foreignKey != "" {
 								associationForeignKeys = strings.Split(foreignKey, ",")
-							} else if foreignKey := field.TagSettings["ASSOCIATIONFOREIGNKEY"]; foreignKey != "" {
+							} else if foreignKey, _ := field.TagSettingsGet("ASSOCIATIONFOREIGNKEY"); foreignKey != "" {
 								associationForeignKeys = strings.Split(foreignKey, ",")
 							}
 
@@ -242,13 +287,13 @@ func (scope *Scope) GetModelStruct() *ModelStruct {
 							}
 
 							if elemType.Kind() == reflect.Struct {
-								if many2many := field.TagSettings["MANY2MANY"]; many2many != "" {
+								if many2many, _ := field.TagSettingsGet("MANY2MANY"); many2many != "" {
 									relationship.Kind = "many_to_many"
 
 									{ // Foreign Keys for Source
 										joinTableDBNames := []string{}
 
-										if foreignKey := field.TagSettings["JOINTABLE_FOREIGNKEY"]; foreignKey != "" {
+										if foreignKey, _ := field.TagSettingsGet("JOINTABLE_FOREIGNKEY"); foreignKey != "" {
 											joinTableDBNames = strings.Split(foreignKey, ",")
 										}
 
@@ -269,7 +314,7 @@ func (scope *Scope) GetModelStruct() *ModelStruct {
 													// if defined join table's foreign key
 													relationship.ForeignDBNames = append(relationship.ForeignDBNames, joinTableDBNames[idx])
 												} else {
-													defaultJointableForeignKey := ToDBName(reflectType.Name()) + "_" + foreignField.DBName
+													defaultJointableForeignKey := ToColumnName(reflectType.Name()) + "_" + foreignField.DBName
 													relationship.ForeignDBNames = append(relationship.ForeignDBNames, defaultJointableForeignKey)
 												}
 											}
@@ -279,7 +324,7 @@ func (scope *Scope) GetModelStruct() *ModelStruct {
 									{ // Foreign Keys for Association (Destination)
 										associationJoinTableDBNames := []string{}
 
-										if foreignKey := field.TagSettings["ASSOCIATION_JOINTABLE_FOREIGNKEY"]; foreignKey != "" {
+										if foreignKey, _ := field.TagSettingsGet("ASSOCIATION_JOINTABLE_FOREIGNKEY"); foreignKey != "" {
 											associationJoinTableDBNames = strings.Split(foreignKey, ",")
 										}
 
@@ -300,7 +345,7 @@ func (scope *Scope) GetModelStruct() *ModelStruct {
 													relationship.AssociationForeignDBNames = append(relationship.AssociationForeignDBNames, associationJoinTableDBNames[idx])
 												} else {
 													// join table foreign keys for association
-													joinTableDBName := ToDBName(elemType.Name()) + "_" + field.DBName
+													joinTableDBName := ToColumnName(elemType.Name()) + "_" + field.DBName
 													relationship.AssociationForeignDBNames = append(relationship.AssociationForeignDBNames, joinTableDBName)
 												}
 											}
@@ -317,7 +362,7 @@ func (scope *Scope) GetModelStruct() *ModelStruct {
 									var toFields = toScope.GetStructFields()
 									relationship.Kind = "has_many"
 
-									if polymorphic := field.TagSettings["POLYMORPHIC"]; polymorphic != "" {
+									if polymorphic, _ := field.TagSettingsGet("POLYMORPHIC"); polymorphic != "" {
 										// Dog has many toys, tag polymorphic is Owner, then associationType is Owner
 										// Toy use OwnerID, OwnerType ('dogs') as foreign key
 										if polymorphicType := getForeignField(polymorphic+"Type", toFields); polymorphicType != nil {
@@ -325,7 +370,7 @@ func (scope *Scope) GetModelStruct() *ModelStruct {
 											relationship.PolymorphicType = polymorphicType.Name
 											relationship.PolymorphicDBName = polymorphicType.DBName
 											// if Dog has multiple set of toys set name of the set (instead of default 'dogs')
-											if value, ok := field.TagSettings["POLYMORPHIC_VALUE"]; ok {
+											if value, ok := field.TagSettingsGet("POLYMORPHIC_VALUE"); ok {
 												relationship.PolymorphicValue = value
 											} else {
 												relationship.PolymorphicValue = scope.TableName()
@@ -407,17 +452,17 @@ func (scope *Scope) GetModelStruct() *ModelStruct {
 								tagAssociationForeignKeys []string
 							)
 
-							if foreignKey := field.TagSettings["FOREIGNKEY"]; foreignKey != "" {
+							if foreignKey, _ := field.TagSettingsGet("FOREIGNKEY"); foreignKey != "" {
 								tagForeignKeys = strings.Split(foreignKey, ",")
 							}
 
-							if foreignKey := field.TagSettings["ASSOCIATION_FOREIGNKEY"]; foreignKey != "" {
+							if foreignKey, _ := field.TagSettingsGet("ASSOCIATION_FOREIGNKEY"); foreignKey != "" {
 								tagAssociationForeignKeys = strings.Split(foreignKey, ",")
-							} else if foreignKey := field.TagSettings["ASSOCIATIONFOREIGNKEY"]; foreignKey != "" {
+							} else if foreignKey, _ := field.TagSettingsGet("ASSOCIATIONFOREIGNKEY"); foreignKey != "" {
 								tagAssociationForeignKeys = strings.Split(foreignKey, ",")
 							}
 
-							if polymorphic := field.TagSettings["POLYMORPHIC"]; polymorphic != "" {
+							if polymorphic, _ := field.TagSettingsGet("POLYMORPHIC"); polymorphic != "" {
 								// Cat has one toy, tag polymorphic is Owner, then associationType is Owner
 								// Toy use OwnerID, OwnerType ('cats') as foreign key
 								if polymorphicType := getForeignField(polymorphic+"Type", toFields); polymorphicType != nil {
@@ -425,7 +470,7 @@ func (scope *Scope) GetModelStruct() *ModelStruct {
 									relationship.PolymorphicType = polymorphicType.Name
 									relationship.PolymorphicDBName = polymorphicType.DBName
 									// if Cat has several different types of toys set name for each (instead of default 'cats')
-									if value, ok := field.TagSettings["POLYMORPHIC_VALUE"]; ok {
+									if value, ok := field.TagSettingsGet("POLYMORPHIC_VALUE"); ok {
 										relationship.PolymorphicValue = value
 									} else {
 										relationship.PolymorphicValue = scope.TableName()
@@ -563,10 +608,10 @@ func (scope *Scope) GetModelStruct() *ModelStruct {
 			}
 
 			// Even it is ignored, also possible to decode db value into the field
-			if value, ok := field.TagSettings["COLUMN"]; ok {
+			if value, ok := field.TagSettingsGet("COLUMN"); ok {
 				field.DBName = value
 			} else {
-				field.DBName = ToDBName(fieldStruct.Name)
+				field.DBName = ToColumnName(fieldStruct.Name)
 			}
 
 			modelStruct.StructFields = append(modelStruct.StructFields, field)
@@ -580,7 +625,7 @@ func (scope *Scope) GetModelStruct() *ModelStruct {
 		}
 	}
 
-	modelStructsMap.Store(reflectType, &modelStruct)
+	modelStructsMap.Store(hashKey, &modelStruct)
 
 	return &modelStruct
 }
@@ -593,6 +638,9 @@ func (scope *Scope) GetStructFields() (fields []*StructField) {
 func parseTagSetting(tags reflect.StructTag) map[string]string {
 	setting := map[string]string{}
 	for _, str := range []string{tags.Get("sql"), tags.Get("gorm")} {
+		if str == "" {
+			continue
+		}
 		tags := strings.Split(str, ";")
 		for _, value := range tags {
 			v := strings.Split(value, ":")

naming.go

@@ -0,0 +1,124 @@
+package gorm
+
+import (
+	"bytes"
+	"strings"
+)
+
+// Namer is a function type which is given a string and return a string
+type Namer func(string) string
+
+// NamingStrategy represents naming strategies
+type NamingStrategy struct {
+	DB     Namer
+	Table  Namer
+	Column Namer
+}
+
+// TheNamingStrategy is being initialized with defaultNamingStrategy
+var TheNamingStrategy = &NamingStrategy{
+	DB:     defaultNamer,
+	Table:  defaultNamer,
+	Column: defaultNamer,
+}
+
+// AddNamingStrategy sets the naming strategy
+func AddNamingStrategy(ns *NamingStrategy) {
+	if ns.DB == nil {
+		ns.DB = defaultNamer
+	}
+	if ns.Table == nil {
+		ns.Table = defaultNamer
+	}
+	if ns.Column == nil {
+		ns.Column = defaultNamer
+	}
+	TheNamingStrategy = ns
+}
+
+// DBName alters the given name by DB
+func (ns *NamingStrategy) DBName(name string) string {
+	return ns.DB(name)
+}
+
+// TableName alters the given name by Table
+func (ns *NamingStrategy) TableName(name string) string {
+	return ns.Table(name)
+}
+
+// ColumnName alters the given name by Column
+func (ns *NamingStrategy) ColumnName(name string) string {
+	return ns.Column(name)
+}
+
+// ToDBName convert string to db name
+func ToDBName(name string) string {
+	return TheNamingStrategy.DBName(name)
+}
+
+// ToTableName convert string to table name
+func ToTableName(name string) string {
+	return TheNamingStrategy.TableName(name)
+}
+
+// ToColumnName convert string to db name
+func ToColumnName(name string) string {
+	return TheNamingStrategy.ColumnName(name)
+}
+
+var smap = newSafeMap()
+
+func defaultNamer(name string) string {
+	const (
+		lower = false
+		upper = true
+	)
+
+	if v := smap.Get(name); v != "" {
+		return v
+	}
+
+	if name == "" {
+		return ""
+	}
+
+	var (
+		value                                    = commonInitialismsReplacer.Replace(name)
+		buf                                      = bytes.NewBufferString("")
+		lastCase, currCase, nextCase, nextNumber bool
+	)
+
+	for i, v := range value[:len(value)-1] {
+		nextCase = bool(value[i+1] >= 'A' && value[i+1] <= 'Z')
+		nextNumber = bool(value[i+1] >= '0' && value[i+1] <= '9')
+
+		if i > 0 {
+			if currCase == upper {
+				if lastCase == upper && (nextCase == upper || nextNumber == upper) {
+					buf.WriteRune(v)
+				} else {
+					if value[i-1] != '_' && value[i+1] != '_' {
+						buf.WriteRune('_')
+					}
+					buf.WriteRune(v)
+				}
+			} else {
+				buf.WriteRune(v)
+				if i == len(value)-2 && (nextCase == upper && nextNumber == lower) {
+					buf.WriteRune('_')
+				}
+			}
+		} else {
+			currCase = upper
+			buf.WriteRune(v)
+		}
+		lastCase = currCase
+		currCase = nextCase
+	}
+
+	buf.WriteByte(value[len(value)-1])
+
+	s := strings.ToLower(buf.String())
+	smap.Set(name, s)
+	return s
+}

naming_test.go

@@ -0,0 +1,69 @@
+package gorm_test
+
+import (
+	"testing"
+
+	"github.com/jinzhu/gorm"
+)
+
+func TestTheNamingStrategy(t *testing.T) {
+
+	cases := []struct {
+		name     string
+		namer    gorm.Namer
+		expected string
+	}{
+		{name: "auth", expected: "auth", namer: gorm.TheNamingStrategy.DB},
+		{name: "userRestrictions", expected: "user_restrictions", namer: gorm.TheNamingStrategy.Table},
+		{name: "clientID", expected: "client_id", namer: gorm.TheNamingStrategy.Column},
+	}
+
+	for _, c := range cases {
+		t.Run(c.name, func(t *testing.T) {
+			result := c.namer(c.name)
+			if result != c.expected {
+				t.Errorf("error in naming strategy. expected: %v got :%v\n", c.expected, result)
+			}
+		})
+	}
+
+}
+
+func TestNamingStrategy(t *testing.T) {
+
+	dbNameNS := func(name string) string {
+		return "db_" + name
+	}
+	tableNameNS := func(name string) string {
+		return "tbl_" + name
+	}
+	columnNameNS := func(name string) string {
+		return "col_" + name
+	}
+
+	ns := &gorm.NamingStrategy{
+		DB:     dbNameNS,
+		Table:  tableNameNS,
+		Column: columnNameNS,
+	}
+
+	cases := []struct {
+		name     string
+		namer    gorm.Namer
+		expected string
+	}{
+		{name: "auth", expected: "db_auth", namer: ns.DB},
+		{name: "user", expected: "tbl_user", namer: ns.Table},
+		{name: "password", expected: "col_password", namer: ns.Column},
+	}
+
+	for _, c := range cases {
+		t.Run(c.name, func(t *testing.T) {
+			result := c.namer(c.name)
+			if result != c.expected {
+				t.Errorf("error in naming strategy. expected: %v got :%v\n", c.expected, result)
+			}
+		})
+	}
+
+}

preload_test.go

@@ -771,6 +771,7 @@ func TestNestedPreload11(t *testing.T) {
 	levelB3 := &LevelB3{
 		Value:     "bar",
 		LevelB1ID: sql.NullInt64{Valid: true, Int64: int64(levelB1.ID)},
+		LevelB2s:  []*LevelB2{},
 	}
 	if err := DB.Create(levelB3).Error; err != nil {
 		t.Error(err)
@@ -1676,7 +1677,7 @@ func TestPreloadManyToManyCallbacks(t *testing.T) {
 	lvl := Level1{
 		Name: "l1",
 		Level2s: []Level2{
-			Level2{Name: "l2-1"}, Level2{Name: "l2-2"},
+			{Name: "l2-1"}, {Name: "l2-2"},
 		},
 	}
 	DB.Save(&lvl)

scope.go

@@ -68,7 +68,7 @@ func (scope *Scope) Dialect() Dialect {
 
 // Quote used to quote string to escape them for database
 func (scope *Scope) Quote(str string) string {
-	if strings.Index(str, ".") != -1 {
+	if strings.Contains(str, ".") {
 		newStrs := []string{}
 		for _, str := range strings.Split(str, ".") {
 			newStrs = append(newStrs, scope.Dialect().Quote(str))
@@ -134,7 +134,7 @@ func (scope *Scope) Fields() []*Field {
 // FieldByName find `gorm.Field` with field name or db name
 func (scope *Scope) FieldByName(name string) (field *Field, ok bool) {
 	var (
-		dbName           = ToDBName(name)
+		dbName           = ToColumnName(name)
 		mostMatchedField *Field
 	)
 
@@ -330,7 +330,7 @@ func (scope *Scope) TableName() string {
 // QuotedTableName return quoted table name
 func (scope *Scope) QuotedTableName() (name string) {
 	if scope.Search != nil && len(scope.Search.tableName) > 0 {
-		if strings.Index(scope.Search.tableName, " ") != -1 {
+		if strings.Contains(scope.Search.tableName, " ") {
 			return scope.Search.tableName
 		}
 		return scope.Quote(scope.Search.tableName)
@@ -358,7 +358,7 @@ func (scope *Scope) Raw(sql string) *Scope {
 
 // Exec perform generated SQL
 func (scope *Scope) Exec() *Scope {
-	defer scope.trace(NowFunc())
+	defer scope.trace(scope.db.nowFunc())
 
 	if !scope.HasError() {
 		if result, err := scope.SQLDB().Exec(scope.SQL, scope.SQLVars...); scope.Err(err) == nil {
@@ -402,7 +402,7 @@ func (scope *Scope) InstanceGet(name string) (interface{}, bool) {
 // Begin start a transaction
 func (scope *Scope) Begin() *Scope {
 	if db, ok := scope.SQLDB().(sqlDb); ok {
-		if tx, err := db.Begin(); err == nil {
+		if tx, err := db.Begin(); scope.Err(err) == nil {
 			scope.db.db = interface{}(tx).(SQLCommon)
 			scope.InstanceSet("gorm:started_transaction", true)
 		}
@@ -486,8 +486,10 @@ func (scope *Scope) scan(rows *sql.Rows, columns []string, fields []*Field) {
 		values[index] = &ignored
 
 		selectFields = fields
+		offset := 0
 		if idx, ok := selectedColumnsMap[column]; ok {
-			selectFields = selectFields[idx+1:]
+			offset = idx + 1
+			selectFields = selectFields[offset:]
 		}
 
 		for fieldIndex, field := range selectFields {
@@ -501,7 +503,7 @@ func (scope *Scope) scan(rows *sql.Rows, columns []string, fields []*Field) {
 					resetFields[index] = field
 				}
 
-				selectedColumnsMap[column] = fieldIndex
+				selectedColumnsMap[column] = offset + fieldIndex
 
 				if field.IsNormal {
 					break
@@ -853,6 +855,14 @@ func (scope *Scope) inlineCondition(values ...interface{}) *Scope {
 }
 
 func (scope *Scope) callCallbacks(funcs []*func(s *Scope)) *Scope {
+	defer func() {
+		if err := recover(); err != nil {
+			if db, ok := scope.db.db.(sqlTx); ok {
+				db.Rollback()
+			}
+			panic(err)
+		}
+	}()
 	for _, f := range funcs {
 		(*f)(scope)
 		if scope.skipLeft {
@@ -862,7 +872,7 @@ func (scope *Scope) callCallbacks(funcs []*func(s *Scope)) *Scope {
 	return scope
 }
 
-func convertInterfaceToMap(values interface{}, withIgnoredField bool) map[string]interface{} {
+func convertInterfaceToMap(values interface{}, withIgnoredField bool, db *DB) map[string]interface{} {
 	var attrs = map[string]interface{}{}
 
 	switch value := values.(type) {
@@ -870,7 +880,7 @@ func convertInterfaceToMap(values interface{}, withIgnoredField bool) map[string
 		return value
 	case []interface{}:
 		for _, v := range value {
-			for key, value := range convertInterfaceToMap(v, withIgnoredField) {
+			for key, value := range convertInterfaceToMap(v, withIgnoredField, db) {
 				attrs[key] = value
 			}
 		}
@@ -880,10 +890,10 @@ func convertInterfaceToMap(values interface{}, withIgnoredField bool) map[string
 		switch reflectValue.Kind() {
 		case reflect.Map:
 			for _, key := range reflectValue.MapKeys() {
-				attrs[ToDBName(key.Interface().(string))] = reflectValue.MapIndex(key).Interface()
+				attrs[ToColumnName(key.Interface().(string))] = reflectValue.MapIndex(key).Interface()
 			}
 		default:
-			for _, field := range (&Scope{Value: values}).Fields() {
+			for _, field := range (&Scope{Value: values, db: db}).Fields() {
 				if !field.IsBlank && (withIgnoredField || !field.IsIgnored) {
 					attrs[field.DBName] = field.Field.Interface()
 				}
@@ -895,19 +905,19 @@ func convertInterfaceToMap(values interface{}, withIgnoredField bool) map[string
 
 func (scope *Scope) updatedAttrsWithValues(value interface{}) (results map[string]interface{}, hasUpdate bool) {
 	if scope.IndirectValue().Kind() != reflect.Struct {
-		return convertInterfaceToMap(value, false), true
+		return convertInterfaceToMap(value, false, scope.db), true
 	}
 
 	results = map[string]interface{}{}
 
-	for key, value := range convertInterfaceToMap(value, true) {
+	for key, value := range convertInterfaceToMap(value, true, scope.db) {
 		if field, ok := scope.FieldByName(key); ok && scope.changeableField(field) {
 			if _, ok := value.(*expr); ok {
 				hasUpdate = true
 				results[field.DBName] = value
 			} else {
 				err := field.Set(value)
-				if field.IsNormal {
+				if field.IsNormal && !field.IsIgnored {
 					hasUpdate = true
 					if err == ErrUnaddressable {
 						results[field.DBName] = value
@@ -922,7 +932,7 @@ func (scope *Scope) updatedAttrsWithValues(value interface{}) (results map[strin
 }
 
 func (scope *Scope) row() *sql.Row {
-	defer scope.trace(NowFunc())
+	defer scope.trace(scope.db.nowFunc())
 
 	result := &RowQueryResult{}
 	scope.InstanceSet("row_query_result", result)
@@ -932,7 +942,7 @@ func (scope *Scope) row() *sql.Row {
 }
 
 func (scope *Scope) rows() (*sql.Rows, error) {
-	defer scope.trace(NowFunc())
+	defer scope.trace(scope.db.nowFunc())
 
 	result := &RowsQueryResult{}
 	scope.InstanceSet("row_query_result", result)
@@ -974,6 +984,10 @@ func (scope *Scope) pluck(column string, value interface{}) *Scope {
 		return scope
 	}
 
+	if dest.Len() > 0 {
+		dest.Set(reflect.Zero(dest.Type()))
+	}
+
 	if query, ok := scope.Search.selects["query"]; !ok || !scope.isQueryForColumn(query, column) {
 		scope.Search.Select(column)
 	}
@@ -997,8 +1011,15 @@ func (scope *Scope) pluck(column string, value interface{}) *Scope {
 func (scope *Scope) count(value interface{}) *Scope {
 	if query, ok := scope.Search.selects["query"]; !ok || !countingQueryRegexp.MatchString(fmt.Sprint(query)) {
 		if len(scope.Search.group) != 0 {
-			scope.Search.Select("count(*) FROM ( SELECT count(*) as name ")
+			if len(scope.Search.havingConditions) != 0 {
-			scope.Search.group += " ) AS count_table"
+				scope.prepareQuerySQL()
+				scope.Search = &search{}
+				scope.Search.Select("count(*)")
+				scope.Search.Table(fmt.Sprintf("( %s ) AS count_table", scope.SQL))
+			} else {
+				scope.Search.Select("count(*) FROM ( SELECT count(*) as name ")
+				scope.Search.group += " ) AS count_table"
+			}
 		} else {
 			scope.Search.Select("count(*)")
 		}
@@ -1113,8 +1134,8 @@ func (scope *Scope) createJoinTable(field *StructField) {
 				if field, ok := scope.FieldByName(fieldName); ok {
 					foreignKeyStruct := field.clone()
 					foreignKeyStruct.IsPrimaryKey = false
-					foreignKeyStruct.TagSettings["IS_JOINTABLE_FOREIGNKEY"] = "true"
+					foreignKeyStruct.TagSettingsSet("IS_JOINTABLE_FOREIGNKEY", "true")
-					delete(foreignKeyStruct.TagSettings, "AUTO_INCREMENT")
+					foreignKeyStruct.TagSettingsDelete("AUTO_INCREMENT")
 					sqlTypes = append(sqlTypes, scope.Quote(relationship.ForeignDBNames[idx])+" "+scope.Dialect().DataTypeOf(foreignKeyStruct))
 					primaryKeys = append(primaryKeys, scope.Quote(relationship.ForeignDBNames[idx]))
 				}
@@ -1124,8 +1145,8 @@ func (scope *Scope) createJoinTable(field *StructField) {
 				if field, ok := toScope.FieldByName(fieldName); ok {
 					foreignKeyStruct := field.clone()
 					foreignKeyStruct.IsPrimaryKey = false
-					foreignKeyStruct.TagSettings["IS_JOINTABLE_FOREIGNKEY"] = "true"
+					foreignKeyStruct.TagSettingsSet("IS_JOINTABLE_FOREIGNKEY", "true")
-					delete(foreignKeyStruct.TagSettings, "AUTO_INCREMENT")
+					foreignKeyStruct.TagSettingsDelete("AUTO_INCREMENT")
 					sqlTypes = append(sqlTypes, scope.Quote(relationship.AssociationForeignDBNames[idx])+" "+scope.Dialect().DataTypeOf(foreignKeyStruct))
 					primaryKeys = append(primaryKeys, scope.Quote(relationship.AssociationForeignDBNames[idx]))
 				}
@@ -1173,7 +1194,7 @@ func (scope *Scope) createTable() *Scope {
 }
 
 func (scope *Scope) dropTable() *Scope {
-	scope.Raw(fmt.Sprintf("DROP TABLE %v%s", scope.QuotedTableName(), scope.getTableOptions())).Exec()
+	scope.Raw(fmt.Sprintf("DROP TABLE %v", scope.QuotedTableName())).Exec()
 	return scope
 }
 
@@ -1260,25 +1281,27 @@ func (scope *Scope) autoIndex() *Scope {
 	var uniqueIndexes = map[string][]string{}
 
 	for _, field := range scope.GetStructFields() {
-		if name, ok := field.TagSettings["INDEX"]; ok {
+		if name, ok := field.TagSettingsGet("INDEX"); ok {
 			names := strings.Split(name, ",")
 
 			for _, name := range names {
 				if name == "INDEX" || name == "" {
 					name = scope.Dialect().BuildKeyName("idx", scope.TableName(), field.DBName)
 				}
-				indexes[name] = append(indexes[name], field.DBName)
+				name, column := scope.Dialect().NormalizeIndexAndColumn(name, field.DBName)
+				indexes[name] = append(indexes[name], column)
 			}
 		}
 
-		if name, ok := field.TagSettings["UNIQUE_INDEX"]; ok {
+		if name, ok := field.TagSettingsGet("UNIQUE_INDEX"); ok {
 			names := strings.Split(name, ",")
 
 			for _, name := range names {
 				if name == "UNIQUE_INDEX" || name == "" {
 					name = scope.Dialect().BuildKeyName("uix", scope.TableName(), field.DBName)
 				}
-				uniqueIndexes[name] = append(uniqueIndexes[name], field.DBName)
+				name, column := scope.Dialect().NormalizeIndexAndColumn(name, field.DBName)
+				uniqueIndexes[name] = append(uniqueIndexes[name], column)
 			}
 		}
 	}
@@ -1299,6 +1322,7 @@ func (scope *Scope) autoIndex() *Scope {
 }
 
 func (scope *Scope) getColumnAsArray(columns []string, values ...interface{}) (results [][]interface{}) {
+	resultMap := make(map[string][]interface{})
 	for _, value := range values {
 		indirectValue := indirect(reflect.ValueOf(value))
 
@@ -1317,7 +1341,10 @@ func (scope *Scope) getColumnAsArray(columns []string, values ...interface{}) (r
 				}
 
 				if hasValue {
-					results = append(results, result)
+					h := fmt.Sprint(result...)
+					if _, exist := resultMap[h]; !exist {
+						resultMap[h] = result
+					}
 				}
 			}
 		case reflect.Struct:
@@ -1332,11 +1359,16 @@ func (scope *Scope) getColumnAsArray(columns []string, values ...interface{}) (r
 			}
 
 			if hasValue {
-				results = append(results, result)
+				h := fmt.Sprint(result...)
+				if _, exist := resultMap[h]; !exist {
+					resultMap[h] = result
+				}
 			}
 		}
 	}
-
+	for _, v := range resultMap {
+		results = append(results, v)
+	}
 	return
 }
 

scope_test.go

@@ -78,3 +78,16 @@ func TestFailedValuer(t *testing.T) {
 		t.Errorf("The error should be returned from Valuer, but get %v", err)
 	}
 }
+
+func TestDropTableWithTableOptions(t *testing.T) {
+	type UserWithOptions struct {
+		gorm.Model
+	}
+	DB.AutoMigrate(&UserWithOptions{})
+
+	DB = DB.Set("gorm:table_options", "CHARSET=utf8")
+	err := DB.DropTable(&UserWithOptions{}).Error
+	if err != nil {
+		t.Errorf("Table must be dropped, got error %s", err)
+	}
+}

utils.go

@@ -1,7 +1,6 @@
 package gorm
 
 import (
-	"bytes"
 	"database/sql/driver"
 	"fmt"
 	"reflect"
@@ -26,8 +25,8 @@ var NowFunc = func() time.Time {
 var commonInitialisms = []string{"API", "ASCII", "CPU", "CSS", "DNS", "EOF", "GUID", "HTML", "HTTP", "HTTPS", "ID", "IP", "JSON", "LHS", "QPS", "RAM", "RHS", "RPC", "SLA", "SMTP", "SSH", "TLS", "TTL", "UID", "UI", "UUID", "URI", "URL", "UTF8", "VM", "XML", "XSRF", "XSS"}
 var commonInitialismsReplacer *strings.Replacer
 
-var goSrcRegexp = regexp.MustCompile(`jinzhu/gorm/.*.go`)
+var goSrcRegexp = regexp.MustCompile(`jinzhu/gorm(@.*)?/.*.go`)
-var goTestRegexp = regexp.MustCompile(`jinzhu/gorm/.*test.go`)
+var goTestRegexp = regexp.MustCompile(`jinzhu/gorm(@.*)?/.*test.go`)
 
 func init() {
 	var commonInitialismsForReplacer []string
@@ -58,66 +57,6 @@ func newSafeMap() *safeMap {
 	return &safeMap{l: new(sync.RWMutex), m: make(map[string]string)}
 }
 
-var smap = newSafeMap()
-
-type strCase bool
-
-const (
-	lower strCase = false
-	upper strCase = true
-)
-
-// ToDBName convert string to db name
-func ToDBName(name string) string {
-	if v := smap.Get(name); v != "" {
-		return v
-	}
-
-	if name == "" {
-		return ""
-	}
-
-	var (
-		value                                    = commonInitialismsReplacer.Replace(name)
-		buf                                      = bytes.NewBufferString("")
-		lastCase, currCase, nextCase, nextNumber strCase
-	)
-
-	for i, v := range value[:len(value)-1] {
-		nextCase = strCase(value[i+1] >= 'A' && value[i+1] <= 'Z')
-		nextNumber = strCase(value[i+1] >= '0' && value[i+1] <= '9')
-
-		if i > 0 {
-			if currCase == upper {
-				if lastCase == upper && (nextCase == upper || nextNumber == upper) {
-					buf.WriteRune(v)
-				} else {
-					if value[i-1] != '_' && value[i+1] != '_' {
-						buf.WriteRune('_')
-					}
-					buf.WriteRune(v)
-				}
-			} else {
-				buf.WriteRune(v)
-				if i == len(value)-2 && (nextCase == upper && nextNumber == lower) {
-					buf.WriteRune('_')
-				}
-			}
-		} else {
-			currCase = upper
-			buf.WriteRune(v)
-		}
-		lastCase = currCase
-		currCase = nextCase
-	}
-
-	buf.WriteByte(value[len(value)-1])
-
-	s := strings.ToLower(buf.String())
-	smap.Set(name, s)
-	return s
-}
-
 // SQL expression
 type expr struct {
 	expr string
@@ -267,7 +206,7 @@ func getValueFromFields(value reflect.Value, fieldNames []string) (results []int
 	// as FieldByName could panic
 	if indirectValue := reflect.Indirect(value); indirectValue.IsValid() {
 		for _, fieldName := range fieldNames {
-			if fieldValue := indirectValue.FieldByName(fieldName); fieldValue.IsValid() {
+			if fieldValue := reflect.Indirect(indirectValue.FieldByName(fieldName)); fieldValue.IsValid() {
 				result := fieldValue.Interface()
 				if r, ok := result.(driver.Valuer); ok {
 					result, _ = r.Value()

utils_test.go

@@ -1,35 +0,0 @@
-package gorm_test
-
-import (
-	"testing"
-
-	"github.com/jinzhu/gorm"
-)
-
-func TestToDBNameGenerateFriendlyName(t *testing.T) {
-	var maps = map[string]string{
-		"":                          "",
-		"X":                         "x",
-		"ThisIsATest":               "this_is_a_test",
-		"PFAndESI":                  "pf_and_esi",
-		"AbcAndJkl":                 "abc_and_jkl",
-		"EmployeeID":                "employee_id",
-		"SKU_ID":                    "sku_id",
-		"UTF8":                      "utf8",
-		"Level1":                    "level1",
-		"SHA256Hash":                "sha256_hash",
-		"FieldX":                    "field_x",
-		"HTTPAndSMTP":               "http_and_smtp",
-		"HTTPServerHandlerForURLID": "http_server_handler_for_url_id",
-		"UUID":     "uuid",
-		"HTTPURL":  "http_url",
-		"HTTP_URL": "http_url",
-		"ThisIsActuallyATestSoWeMayBeAbleToUseThisCodeInGormPackageAlsoIdCanBeUsedAtTheEndAsID": "this_is_actually_a_test_so_we_may_be_able_to_use_this_code_in_gorm_package_also_id_can_be_used_at_the_end_as_id",
-	}
-
-	for key, value := range maps {
-		if gorm.ToDBName(key) != value {
-			t.Errorf("%v ToDBName should equal %v, but got %v", key, value, gorm.ToDBName(key))
-		}
-	}
-}

wercker.yml

@@ -9,6 +9,13 @@ services:
           MYSQL_USER: gorm
           MYSQL_PASSWORD: gorm
           MYSQL_RANDOM_ROOT_PASSWORD: "yes"
+    - name: mysql
+      id: mysql:latest
+      env:
+          MYSQL_DATABASE: gorm
+          MYSQL_USER: gorm
+          MYSQL_PASSWORD: gorm
+          MYSQL_RANDOM_ROOT_PASSWORD: "yes"
     - name: mysql57
       id: mysql:5.7
       env:
@@ -23,13 +30,6 @@ services:
           MYSQL_USER: gorm
           MYSQL_PASSWORD: gorm
           MYSQL_RANDOM_ROOT_PASSWORD: "yes"
-    - name: mysql55
-      id: mysql:5.5
-      env:
-          MYSQL_DATABASE: gorm
-          MYSQL_USER: gorm
-          MYSQL_PASSWORD: gorm
-          MYSQL_RANDOM_ROOT_PASSWORD: "yes"
     - name: postgres
       id: postgres:latest
       env:
@@ -83,7 +83,7 @@ build:
                 code: |
                     cd $WERCKER_SOURCE_DIR
                     go version
-                    go get -t ./...
+                    go get -t -v ./...
 
         # Build the project
         - script:
@@ -95,54 +95,60 @@ build:
         - script:
                 name: test sqlite
                 code: |
-                    go test ./...
+                    go test -race -v ./...
 
         - script:
                 name: test mariadb
                 code: |
-                    GORM_DIALECT=mysql GORM_DSN="gorm:gorm@tcp(mariadb:3306)/gorm?charset=utf8&parseTime=True" go test ./...
+                    GORM_DIALECT=mysql GORM_DSN="gorm:gorm@tcp(mariadb:3306)/gorm?charset=utf8&parseTime=True" go test -race ./...
+
+        - script:
+                name: test mysql
+                code: |
+                    GORM_DIALECT=mysql GORM_DSN="gorm:gorm@tcp(mysql:3306)/gorm?charset=utf8&parseTime=True" go test -race ./...
 
         - script:
                 name: test mysql5.7
                 code: |
-                    GORM_DIALECT=mysql GORM_DSN="gorm:gorm@tcp(mysql57:3306)/gorm?charset=utf8&parseTime=True" go test ./...
+                    GORM_DIALECT=mysql GORM_DSN="gorm:gorm@tcp(mysql57:3306)/gorm?charset=utf8&parseTime=True" go test -race ./...
 
         - script:
                 name: test mysql5.6
                 code: |
-                    GORM_DIALECT=mysql GORM_DSN="gorm:gorm@tcp(mysql56:3306)/gorm?charset=utf8&parseTime=True" go test ./...
+                    GORM_DIALECT=mysql GORM_DSN="gorm:gorm@tcp(mysql56:3306)/gorm?charset=utf8&parseTime=True" go test -race ./...
-
-        - script:
-                name: test mysql5.5
-                code: |
-                    GORM_DIALECT=mysql GORM_DSN="gorm:gorm@tcp(mysql55:3306)/gorm?charset=utf8&parseTime=True" go test ./...
 
         - script:
                 name: test postgres
                 code: |
-                    GORM_DIALECT=postgres GORM_DSN="host=postgres user=gorm password=gorm DB.name=gorm port=5432 sslmode=disable" go test ./...
+                    GORM_DIALECT=postgres GORM_DSN="host=postgres user=gorm password=gorm DB.name=gorm port=5432 sslmode=disable" go test -race ./...
 
         - script:
                 name: test postgres96
                 code: |
-                    GORM_DIALECT=postgres GORM_DSN="host=postgres96 user=gorm password=gorm DB.name=gorm port=5432 sslmode=disable" go test ./...
+                    GORM_DIALECT=postgres GORM_DSN="host=postgres96 user=gorm password=gorm DB.name=gorm port=5432 sslmode=disable" go test -race ./...
 
         - script:
                 name: test postgres95
                 code: |
-                    GORM_DIALECT=postgres GORM_DSN="host=postgres95 user=gorm password=gorm DB.name=gorm port=5432 sslmode=disable" go test ./...
+                    GORM_DIALECT=postgres GORM_DSN="host=postgres95 user=gorm password=gorm DB.name=gorm port=5432 sslmode=disable" go test -race ./...
 
         - script:
                 name: test postgres94
                 code: |
-                    GORM_DIALECT=postgres GORM_DSN="host=postgres94 user=gorm password=gorm DB.name=gorm port=5432 sslmode=disable" go test ./...
+                    GORM_DIALECT=postgres GORM_DSN="host=postgres94 user=gorm password=gorm DB.name=gorm port=5432 sslmode=disable" go test -race ./...
 
         - script:
                 name: test postgres93
                 code: |
-                    GORM_DIALECT=postgres GORM_DSN="host=postgres93 user=gorm password=gorm DB.name=gorm port=5432 sslmode=disable" go test ./...
+                    GORM_DIALECT=postgres GORM_DSN="host=postgres93 user=gorm password=gorm DB.name=gorm port=5432 sslmode=disable" go test -race ./...
 
         - script:
                 name: test mssql
                 code: |
-                    GORM_DIALECT=mssql GORM_DSN="sqlserver://gorm:LoremIpsum86@mssql:1433?database=gorm" go test ./...
+                    GORM_DIALECT=mssql GORM_DSN="sqlserver://gorm:LoremIpsum86@mssql:1433?database=gorm" go test -race ./...
+
+        - script:
+                name: codecov
+                code: |
+                    go test -race -coverprofile=coverage.txt -covermode=atomic ./...
+                    bash <(curl -s https://codecov.io/bash)