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Mysql SQL语句将varchar转换为整数_Mysql_Sql_Syntax Error - Fatal编程技术网

Mysql SQL语句将varchar转换为整数

Mysql SQL语句将varchar转换为整数,mysql,sql,syntax-error,Mysql,Sql,Syntax Error,我在尝试使用SQL语句将MySQL中的varchar字段转换为整数时遇到了一些问题: SELECT mrtpopTime, CONVERT(INT,mrtpopAmt) FROM tm_mrtpop WHERE mrtpopName = '' ORDER BY CONVERT(INT, mrtpopAmt) DESC 当mrtpopAmt以相反的顺序排列时,我正试图获得前三名记录。但是,我在INT处收到错误消息,错误消息为: Syntax error, Unecpected INT_SYM

我在尝试使用SQL语句将MySQL中的varchar字段转换为整数时遇到了一些问题:

SELECT mrtpopTime, CONVERT(INT,mrtpopAmt)
FROM tm_mrtpop
WHERE mrtpopName = ''
ORDER BY CONVERT(INT, mrtpopAmt) DESC
当mrtpopAmt以相反的顺序排列时,我正试图获得前三名记录。但是,我在INT处收到错误消息,错误消息为:

Syntax error, Unecpected INT_SYM

我想知道为什么会这样?提前感谢。

这是因为MySQL不使用
CONVERT()
进行强制转换。它使用函数。在您的情况下,您将使用:

CAST(mrtpopAmt AS SIGNED) -- This can also be UNSIGNED if it will always be a positive integer