bug fixed and code refactoring

mysql_dialect.go

@@ -119,10 +119,13 @@ func (db *mysql) GetColumns(tableName string) ([]string, map[string]*core.Column
 		return nil, nil, err
 	}
 	defer cnn.Close()
+
 	rows, err := cnn.Query(s, args...)
 	if err != nil {
 		return nil, nil, err
 	}
+	defer rows.Close()
+
 	cols := make(map[string]*core.Column)
 	colSeq := make([]string, 0)
 	for rows.Next() {

postgres_dialect.go

@@ -276,23 +276,6 @@ func (db *postgres) GetIndexes(tableName string) (map[string]*core.Index, error)
 	return indexes, nil
 }
 
-// PgSeqFilter filter SQL replace ?, ? ... to $1, $2 ...
-type PgSeqFilter struct {
-}
-
-func (s *PgSeqFilter) Do(sql string, dialect core.Dialect, table *core.Table) string {
-	segs := strings.Split(sql, "?")
-	size := len(segs)
-	res := ""
-	for i, c := range segs {
-		if i < size-1 {
-			res += c + fmt.Sprintf("$%v", i+1)
-		}
-	}
-	res += segs[size-1]
-	return res
-}
-
 func (db *postgres) Filters() []core.Filter {
-	return []core.Filter{&core.IdFilter{}, &core.QuoteFilter{}, &PgSeqFilter{}}
+	return []core.Filter{&core.IdFilter{}, &core.QuoteFilter{}, &core.SeqFilter{"$", 1}}
 }