} else {
				writer.WriteString("(NULL)")
			}
		case interface{ getInstance() *DB }:
			cv := v.getInstance()

			subdb := cv.Session(&Session{Logger: logger.Discard, DryRun: true}).getInstance()
			if cv.Statement.SQL.Len() > 0 {
				var (
					vars = subdb.Statement.Vars
					sql  = cv.Statement.SQL.String()
				)

				subdb.Statement.Vars = make([]interface{}, 0, len(vars))