我正在尝试使用Java中的准备好的语句执行选择查询。
在Where子句中,im检查Timestamp类型列上的条件,如下所示。

String selectSQL = "select * from db.keycontacts WHERE CREATEDDATETIME>?";
PreparedStatement preparedStatement = connect.prepareStatement(selectSQL);
preparedStatement.setTimestamp(1, convertStrToTimestamp(lastSyncTimeStamp));
resultSet = preparedStatement.executeQuery(selectSQL );


//将timestampString转换为java.sql.Timestamp的函数

private java.sql.Timestamp convertStrToTimestamp(String dateTimeStr){

      java.sql.Timestamp timeStampDate = null;
      try {
            DateFormat formatter = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");//2015-05-11 18:26:55
            java.util.Date dateObj = (java.util.Date)formatter.parse(dateTimeStr);
            timeStampDate = new Timestamp(dateObj.getTime());
        } catch (ParseException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

      return timeStampDate;
  }


执行查询时,出现以下异常。

com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '?' at line 1


那么我在哪里错呢?

提前致谢。

最佳答案

从中删除参数

resultSet = preparedStatement.executeQuery(selectSQL );


并更改为

resultSet = preparedStatement.executeQuery( );


preparedStatement.executeQuery(selectSQL );中传递的查询优先于在connect.prepareStatement(selectSQL);中传递的查询,这是您在其中设置任何参数的简单字符串("select * from db.keycontacts WHERE CREATEDDATETIME>?"),因此?会出现语法错误

而且您还可以说该语句是在PreparedStatement preparedStatement = connect.prepareStatement(selectSQL);处准备的,因为executeQuery()是从Statement继承的,它将执行查询而无需准备它。

10-08 16:39