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求一个sql语句

WBOY
Release： 2016-06-23 14:22:19
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mysql 条件计算

表A，字段ax,ay,az
表B，字段bx,by,bz 

$time = time();select *,(A.az*7+B.bz) as exp WHERE exp<='.$time.' ORDER BY A.ay;
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类似这样的 通过计算得到一个临时列exp，然后再去判断exp的值是否小于某个数的SQL语句应该怎么写？我写成这样后提示语法错误：Unknown column 'exp' in 'where clause'


回复讨论(解决方案)

.... (A.az*7+B.bz)<='.$time.'....

SQL是从右到左的，所以where的时候exp还没有定义。

试一试 HAVING 应该是可以 

select *,(A.az*7+B.bz) as exp HAVING exp<='.$time.' ORDER BY A.ay;
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求一个sql语句
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