mysql - 在 mySQL 中对多个相同的表求和

Question

我有 4 个相同的表(每个季度一个)。我已经设法计算每个季度的每个起始终端和按起始终端分组的数量。但是，我想对所有 4 个季度(表格)求和以获得计数总和。

SELECT StartTerminal, COUNT(*)
FROM test.2013_q1
GROUP BY StartTerminal;

Click here to see screenshot

这是我尝试执行但失败的脚本:

SELECT StartTerminal, COUNT(*) as TotalCount
FROM (
    SELECT StartTerminal
    FROM test.2013_q1
    GROUP BY StartTerminal
    UNION ALL
        SELECT StartTerminal
        FROM test.2013_q2
        GROUP BY StartTerminal
    )
    GROUP BY StartTerminal;

谢谢!!

Answer 1

我认为错误可能是您没有为子查询指定名称。请试试这个 -

SELECT StartTerminal, SUM(count) as TotalCount
FROM (
SELECT StartTerminal, COUNT(*) as count
FROM test.2013_q1
GROUP BY StartTerminal
UNION ALL
SELECT StartTerminal, COUNT(*) as count
FROM test.2013_q2
GROUP BY StartTerminal
) all_year_data
GROUP BY StartTerminal;