Add CopyIn for postgres dialect

.gitignore

@@ -1,2 +1,3 @@
 documents
 _book
+.idea/workspace.xml

main.go

@@ -4,6 +4,7 @@ import (
 	"database/sql"
 	"errors"
 	"fmt"
+	"github.com/lib/pq"
 	"reflect"
 	"strings"
 	"sync"
@@ -16,6 +17,10 @@ type DB struct {
 	Error        error
 	RowsAffected int64
 
+	// for copyIn
+	dataSource string
+	copyDB     *sql.DB
+
 	// single db
 	db                SQLCommon
 	blockGlobalUpdate bool
@@ -74,6 +79,7 @@ func Open(dialect string, args ...interface{}) (db *DB, err error) {
 		logger:     defaultLogger,
 		callbacks:  DefaultCallback,
 		dialect:    newDialect(dialect, dbSQL),
+		dataSource: source,
 	}
 	db.parent = db
 	if err != nil {
@@ -96,6 +102,21 @@ func (s *DB) New() *DB {
 	return clone
 }
 
+// DataSource returns its opened dataSource:
+//    gorm.Open("postgres", "host=localhost user=root dbname=test sslmode=disable password=123")
+// Then dataSource = "host=localhost user=root dbname=test sslmode=disable password=123"
+func (s *DB) DataSource() string {
+	return s.dataSource
+}
+
+// CopyDB returns its origin db engine whose driver is github.com/lib/pq
+func (s *DB) CopyDB() (*sql.DB, error) {
+	if s.copyDB != nil {
+		return s.copyDB, nil
+	}
+	return sql.Open(s.Dialect().GetName(), s.DataSource())
+}
+
 type closer interface {
 	Close() error
 }
@@ -462,6 +483,71 @@ func (s *DB) Exec(sql string, values ...interface{}) *DB {
 	return scope.Exec().db
 }
 
+// CopyIn execute a big amount of insertions
+//   closeAfterUsed: After finished or stopped by accident, the copyDB close itself  if 'closeAfterUsed' has been set true
+//   table: which table you want to operate
+//   args: what you want to insert
+//   columns: what column you want to operate
+// For instance:
+//   	args = append(args, []interface{}{
+//			"tom", 9,
+//		}, []interface{}{
+//			"sara", 10,
+//		}, []interface{}{
+//			"jim", 11,
+//		})
+//     db.CopyIn(false, "user", args, "name","age")
+// This stands for 'insert into user(name,age) values('tom', 9),('sara',10),('jim',19)'
+// 				or 'COPY 'user' ('name','age') FROM STDIN`'
+func (s *DB) CopyIn(closeAfterUsed bool, table string, args [][]interface{}, columns ...string) error {
+	if s.Dialect().GetName() != "postgres" {
+		return errors.New("CopyIn only supports postgres")
+	}
+
+	pdb, err := s.CopyDB()
+	if closeAfterUsed {
+		defer pdb.Close()
+	}
+
+	if err != nil {
+		return err
+	}
+	txn, err := pdb.Begin()
+	if err != nil {
+		return err
+	}
+
+	stmt, err := txn.Prepare(pq.CopyIn(table, columns...))
+	if err != nil {
+		return err
+	}
+	for _, v := range args {
+		_, err = stmt.Exec(v...)
+		if err != nil {
+			txn.Rollback()
+			return err
+		}
+	}
+
+	_, err = stmt.Exec()
+	if err != nil {
+		txn.Rollback()
+		return err
+	}
+
+	err = stmt.Close()
+	if err != nil {
+		txn.Rollback()
+		return err
+	}
+	err = txn.Commit()
+	if err != nil {
+		txn.Rollback()
+		return err
+	}
+	return nil
+}
+
 // Model specify the model you would like to run db operations
 //    // update all users's name to `hello`
 //    db.Model(&User{}).Update("name", "hello")

main_test.go

@@ -1059,6 +1059,61 @@ func TestBlockGlobalUpdate(t *testing.T) {
 	}
 }
 
+func TestDB_DataSource(t *testing.T) {
+	source := "user=gorm password=gorm DB.name=gorm port=9920 sslmode=disable"
+	db, er := gorm.Open("postgres", source)
+	if er != nil {
+		panic(fmt.Sprintf("No error should happen when connecting to test database, but got err=%+v", er))
+	}
+	if db.DataSource() != source {
+		t.Fatal(fmt.Sprintf("want '%s', but got '%s'", source, db.DataSource()))
+	}
+
+}
+func TestDB_CopyIn(t *testing.T) {
+	source := "user=gorm password=gorm DB.name=gorm port=9920 sslmode=disable"
+	db, er := gorm.Open("postgres", source)
+	if er != nil {
+		panic(fmt.Sprintf("No error should happen when connecting to test database, but got err=%+v", er))
+	}
+	e := db.Exec("create table if not exists example(name varchar, age integer)").Error
+	defer func() {
+		er := db.Exec("drop table if exists example").Error
+		if er != nil {
+			t.Fatal(e.Error())
+		}
+	}()
+	if e != nil {
+		t.Fatal(e.Error())
+	}
+	defer db.Exec("drop table")
+	var args = make([][]interface{}, 0)
+	args = append(args, []interface{}{
+		"tom", 9,
+	}, []interface{}{
+		"sara", 10,
+	}, []interface{}{
+		"jim", 11,
+	})
+	e = db.CopyIn(true, "example", args, "name", "age")
+	if e != nil {
+		t.Fatal(e.Error())
+	}
+	type Example struct {
+		Name string
+		Age  int
+	}
+	var examples = make([]Example, 0)
+	e = db.Raw("select * from example").Find(&examples).Error
+	if e != nil {
+		t.Fatal(e.Error())
+	}
+	if len(examples) == 0 {
+		t.Fatal("examples length wants more than 3, but got 0")
+	}
+	fmt.Println(examples)
+}
+
 func BenchmarkGorm(b *testing.B) {
 	b.N = 2000
 	for x := 0; x < b.N; x++ {