Add DisableNestedTransaction support

finisher_api.go

@@ -498,6 +498,7 @@ func (db *DB) Transaction(fc func(tx *DB) error, opts ...*sql.TxOptions) (err er
 
 	if committer, ok := db.Statement.ConnPool.(TxCommitter); ok && committer != nil {
 		// nested transaction
+		if !db.DisableNestedTransaction {
 			err = db.SavePoint(fmt.Sprintf("sp%p", fc)).Error
 			defer func() {
 				// Make sure to rollback when panic, Block error or Commit error
@@ -505,6 +506,7 @@ func (db *DB) Transaction(fc func(tx *DB) error, opts ...*sql.TxOptions) (err er
 					db.RollbackTo(fmt.Sprintf("sp%p", fc))
 				}
 			}()
+		}
 
 		if err == nil {
 			err = fc(db.Session(&Session{}))

gorm.go

@@ -34,6 +34,8 @@ type Config struct {
 	DisableAutomaticPing bool
 	// DisableForeignKeyConstraintWhenMigrating
 	DisableForeignKeyConstraintWhenMigrating bool
+	// DisableNestedTransaction disable nested transaction
+	DisableNestedTransaction bool
 	// AllowGlobalUpdate allow global update
 	AllowGlobalUpdate bool
 	// QueryFields executes the SQL query with all fields of the table
@@ -70,6 +72,7 @@ type Session struct {
 	NewDB                    bool
 	SkipHooks                bool
 	SkipDefaultTransaction   bool
+	DisableNestedTransaction bool
 	AllowGlobalUpdate        bool
 	FullSaveAssociations     bool
 	QueryFields              bool
@@ -206,6 +209,10 @@ func (db *DB) Session(config *Session) *DB {
 		tx.Statement.SkipHooks = true
 	}
 
+	if config.DisableNestedTransaction {
+		txConfig.DisableNestedTransaction = true
+	}
+
 	if !config.NewDB {
 		tx.clone = 2
 	}

tests/transaction_test.go

@@ -283,6 +283,69 @@ func TestNestedTransactionWithBlock(t *testing.T) {
 	}
 }
 
+func TestDisabledNestedTransaction(t *testing.T) {
+	var (
+		user  = *GetUser("transaction-nested", Config{})
+		user1 = *GetUser("transaction-nested-1", Config{})
+		user2 = *GetUser("transaction-nested-2", Config{})
+	)
+
+	if err := DB.Session(&gorm.Session{DisableNestedTransaction: true}).Transaction(func(tx *gorm.DB) error {
+		tx.Create(&user)
+
+		if err := tx.First(&User{}, "name = ?", user.Name).Error; err != nil {
+			t.Fatalf("Should find saved record")
+		}
+
+		if err := tx.Transaction(func(tx1 *gorm.DB) error {
+			tx1.Create(&user1)
+
+			if err := tx1.First(&User{}, "name = ?", user1.Name).Error; err != nil {
+				t.Fatalf("Should find saved record")
+			}
+
+			return errors.New("rollback")
+		}); err == nil {
+			t.Fatalf("nested transaction should returns error")
+		}
+
+		if err := tx.First(&User{}, "name = ?", user1.Name).Error; err != nil {
+			t.Fatalf("Should not rollback record if disabled nested transaction support")
+		}
+
+		if err := tx.Transaction(func(tx2 *gorm.DB) error {
+			tx2.Create(&user2)
+
+			if err := tx2.First(&User{}, "name = ?", user2.Name).Error; err != nil {
+				t.Fatalf("Should find saved record")
+			}
+
+			return nil
+		}); err != nil {
+			t.Fatalf("nested transaction returns error: %v", err)
+		}
+
+		if err := tx.First(&User{}, "name = ?", user2.Name).Error; err != nil {
+			t.Fatalf("Should find saved record")
+		}
+		return nil
+	}); err != nil {
+		t.Fatalf("no error should return, but got %v", err)
+	}
+
+	if err := DB.First(&User{}, "name = ?", user.Name).Error; err != nil {
+		t.Fatalf("Should find saved record")
+	}
+
+	if err := DB.First(&User{}, "name = ?", user1.Name).Error; err != nil {
+		t.Fatalf("Should not rollback record if disabled nested transaction support")
+	}
+
+	if err := DB.First(&User{}, "name = ?", user2.Name).Error; err != nil {
+		t.Fatalf("Should find saved record")
+	}
+}
+
 func TestTransactionOnClosedConn(t *testing.T) {
 	DB, err := OpenTestConnection()
 	if err != nil {