php - 如何统计多个表的行 MySQL

Question

我如何计算 2 个表中的所有行...

`approved` == '0'

?

Answer 1

您需要对联合进行聚合:

select sum(subcount) as totalcount 
    from ( select count(*) as subcount from table1 where approved = 0
           union
           select count(*) as subcount from table2 where approved = 0 )

还有其他方法，但这非常清楚地表明了您的意图，尤其是用这种方式命名列。

希望对你有帮助