SELECT
(
SELECT
count(*) AS m1
FROM
table1
) + (
SELECT
count(*) AS m2
FROM
table2
);
select(*): select括号里面的只能为一行一列,否则会报错;
select * from ():可以返回多行多列。
另外mysql不允许1+2这种方式相加,但是可允许两个column相加,即select (column a) +(column b)
mysql多表count累计
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转载自jiangxia207.iteye.com/blog/2307470
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