Reworked CurrentDatabase API to return the name instead of `*gorm.DB'.

common_dialect.go

@@ -71,9 +71,8 @@ func (commonDialect) Quote(key string) string {
 func (c commonDialect) HasTable(scope *Scope, tableName string) bool {
 	var (
 		count        int
-		databaseName string
+		databaseName = c.CurrentDatabase(scope)
 	)
-	c.CurrentDatabase(scope, &databaseName)
 	scope.NewDB().Raw("SELECT count(*) FROM INFORMATION_SCHEMA.TABLES WHERE table_name = ? AND table_schema = ?", tableName, databaseName).Row().Scan(&count)
 	return count > 0
 }
@@ -81,9 +80,8 @@ func (c commonDialect) HasTable(scope *Scope, tableName string) bool {
 func (c commonDialect) HasColumn(scope *Scope, tableName string, columnName string) bool {
 	var (
 		count        int
-		databaseName string
+		databaseName = c.CurrentDatabase(scope)
 	)
-	c.CurrentDatabase(scope, &databaseName)
 	scope.NewDB().Raw("SELECT count(*) FROM INFORMATION_SCHEMA.COLUMNS WHERE table_schema = ? AND table_name = ? AND column_name = ?", databaseName, tableName, columnName).Row().Scan(&count)
 	return count > 0
 }
@@ -98,6 +96,7 @@ func (commonDialect) RemoveIndex(scope *Scope, indexName string) {
 	scope.NewDB().Exec(fmt.Sprintf("DROP INDEX %v ON %v", indexName, scope.QuotedTableName()))
 }
 
-func (commonDialect) CurrentDatabase(scope *Scope, name *string) {
+func (commonDialect) CurrentDatabase(scope *Scope) (name string) {
-	scope.Err(scope.NewDB().Raw("SELECT DATABASE()").Row().Scan(name))
+	scope.Err(scope.NewDB().Raw("SELECT DATABASE()").Row().Scan(&name))
+	return
 }

dialect.go

@@ -17,7 +17,7 @@ type Dialect interface {
 	HasColumn(scope *Scope, tableName string, columnName string) bool
 	HasIndex(scope *Scope, tableName string, indexName string) bool
 	RemoveIndex(scope *Scope, indexName string)
-	CurrentDatabase(scope *Scope, name *string)
+	CurrentDatabase(scope *Scope) string
 }
 
 func NewDialect(driver string) Dialect {

foundation.go

@@ -77,6 +77,7 @@ func (foundation) HasIndex(scope *Scope, tableName string, indexName string) boo
 	return count > 0
 }
 
-func (foundation) CurrentDatabase(scope *Scope, name *string) {
+func (foundation) CurrentDatabase(scope *Scope) (name string) {
-	scope.Err(scope.NewDB().Raw("SELECT CURRENT_SCHEMA").Row().Scan(name))
+	scope.Err(scope.NewDB().Raw("SELECT CURRENT_SCHEMA").Row().Scan(&name))
+	return
 }

main.go

@@ -429,10 +429,12 @@ func (s *DB) RemoveIndex(indexName string) *DB {
 	return scope.db
 }
 
-func (s *DB) CurrentDatabase(name *string) *DB {
+func (s *DB) CurrentDatabase() string {
-	scope := s.clone().NewScope(s.Value)
+	var (
-	s.dialect.CurrentDatabase(scope, name)
+		scope = s.clone().NewScope(s.Value)
-	return scope.db
+		name  = s.dialect.CurrentDatabase(scope)
+	)
+	return name
 }
 
 /*

mssql.go

@@ -53,9 +53,8 @@ func (mssql) SqlTag(value reflect.Value, size int, autoIncrease bool) string {
 func (s mssql) HasTable(scope *Scope, tableName string) bool {
 	var (
 		count        int
-		databaseName string
+		databaseName = s.CurrentDatabase(scope)
 	)
-	s.CurrentDatabase(scope, &databaseName)
 	scope.NewDB().Raw("SELECT count(*) FROM INFORMATION_SCHEMA.tables WHERE table_name = ? AND table_catalog = ?", tableName, databaseName).Row().Scan(&count)
 	return count > 0
 }
@@ -63,9 +62,8 @@ func (s mssql) HasTable(scope *Scope, tableName string) bool {
 func (s mssql) HasColumn(scope *Scope, tableName string, columnName string) bool {
 	var (
 		count        int
-		databaseName string
+		databaseName = s.CurrentDatabase(scope)
 	)
-	s.CurrentDatabase(scope, &databaseName)
 	scope.NewDB().Raw("SELECT count(*) FROM information_schema.columns WHERE table_catalog = ? AND table_name = ? AND column_name = ?", databaseName, tableName, columnName).Row().Scan(&count)
 	return count > 0
 }
@@ -76,6 +74,7 @@ func (mssql) HasIndex(scope *Scope, tableName string, indexName string) bool {
 	return count > 0
 }
 
-func (mssql) CurrentDatabase(scope *Scope, name *string) {
+func (mssql) CurrentDatabase(scope *Scope) (name string) {
-	scope.Err(scope.NewDB().Raw("SELECT DB_NAME() AS [Current Database]").Row().Scan(name))
+	scope.Err(scope.NewDB().Raw("SELECT DB_NAME() AS [Current Database]").Row().Scan(&name))
+	return
 }

mysql.go

@@ -64,6 +64,7 @@ func (mysql) SelectFromDummyTable() string {
 	return "FROM DUAL"
 }
 
-func (mysql) CurrentDatabase(scope *Scope, name *string) {
+func (mysql) CurrentDatabase(scope *Scope) (name string) {
-	scope.Err(scope.NewDB().Raw("SELECT DATABASE()").Row().Scan(name))
+	scope.Err(scope.NewDB().Raw("SELECT DATABASE()").Row().Scan(&name))
+	return
 }

postgres.go

@@ -85,8 +85,9 @@ func (postgres) HasIndex(scope *Scope, tableName string, indexName string) bool
 	return count > 0
 }
 
-func (postgres) CurrentDatabase(scope *Scope, name *string) {
+func (postgres) CurrentDatabase(scope *Scope) (name string) {
-	scope.Err(scope.NewDB().Raw("SELECT CURRENT_DATABASE()").Row().Scan(name))
+	scope.Err(scope.NewDB().Raw("SELECT CURRENT_DATABASE()").Row().Scan(&name))
+	return
 }
 
 var hstoreType = reflect.TypeOf(Hstore{})

query_test.go

@@ -582,12 +582,12 @@ func TestSelectWithArrayInput(t *testing.T) {
 
 func TestCurrentDatabase(t *testing.T) {
 	DB.LogMode(true)
-	var name string
+	databaseName := DB.CurrentDatabase()
-	if err := DB.CurrentDatabase(&name).Error; err != nil {
+	if err := DB.Error; err != nil {
 		t.Errorf("Problem getting current db name: %s", err)
 	}
-	if name == "" {
+	if databaseName == "" {
 		t.Errorf("Current db name returned empty; this should never happen!")
 	}
-	t.Logf("Got current db name: %v", name)
+	t.Logf("Got current db name: %v", databaseName)
 }

sqlite3.go

@@ -62,7 +62,7 @@ func (sqlite3) RemoveIndex(scope *Scope, indexName string) {
 	scope.NewDB().Exec(fmt.Sprintf("DROP INDEX %v", indexName))
 }
 
-func (sqlite3) CurrentDatabase(scope *Scope, name *string) {
+func (sqlite3) CurrentDatabase(scope *Scope) (name string) {
 	var (
 		ifaces   = make([]interface{}, 3)
 		pointers = make([]*string, 3)
@@ -75,6 +75,7 @@ func (sqlite3) CurrentDatabase(scope *Scope, name *string) {
 		return
 	}
 	if pointers[1] != nil {
-		*name = *pointers[1]
+		name = *pointers[1]
 	}
+	return
 }