在多个表中使用COUNT

Question

我有以下代码来计算我的JB_Employer表中的记录数，但我还想将第二个（可能是第三个）表中的记录总数添加到此表中。

SELECT COUNT( * ) AS 'Number of employees'
FROM JB_Employer
WHERE Employer_ID >0

此外，如果有人可以建议我如何把它放到PHP中，我会很感激，有点麻烦搞清楚。

Answer 1

SELECT (
SELECT count(*) from table1
) as `table1_count`, (
SELECT count(*) from table2
) as `table2_count`

如果你想加起来

SELECT (
SELECT count(*) from table1
) + (
SELECT count(*) from table2
) as `total_count`