writer.WriteByte('(')
				stmt.AddVar(writer, v...)
				writer.WriteByte(')')
			} else {
				writer.WriteString("(NULL)")
			}
		case *DB:
			subdb := v.Session(&Session{Logger: logger.Discard, DryRun: true}).getInstance()
			if v.Statement.SQL.Len() > 0 {
				var (
					vars = subdb.Statement.Vars
					sql  = v.Statement.SQL.String()
				)

	Error(context.Context, string, ...interface{})
	Trace(ctx context.Context, begin time.Time, fc func() (sql string, rowsAffected int64), err error)
}

var (
	// Discard logger will print any log to io.Discard
	Discard = New(log.New(io.Discard, "", log.LstdFlags), Config{})
	// Default Default logger
	Default = New(log.New(os.Stdout, "\r\n", log.LstdFlags), Config{
		SlowThreshold:             200 * time.Millisecond,