ERROR 1690 (22003): BIGINT UNSIGNED value is out of range in..的错误 [转]

问题： ERROR 1690 (22003): BIGINT UNSIGNED value is out of range in..的错误

解决方法：

　　把没被singed的变量临时变更signed去处理。

　　select (cast(col1 as signed)-cast(col2 as signed)) asresult fromTable;