Question

您好我有一张桌子（Spiel），其中我有两个列（SpielerIDForderer，SpielerIDGefordert）。从这两个col我想要最多出现的记录并计算在一起。因此，如果值/ id 2在SpielerIDForderer中出现两次，在SpielerIDGefordert中出现七次，则应返回9.

这是我的表

+-------------------+--------------------+
| SpielerIDForderer | SpielerIDGefordert |
+-------------------+--------------------+
|  5                |  2                 |
|  3                |  2                 |
|  3                |  2                 |
|  3                |  8                 |
|  6                |  2                 |
|  3                |  2                 |
|  3                |  2                 |
|  2                |  3                 |
|  2                |  2                 |
+-------------------+--------------------+

这是我的SQL无法正常工作：

SELECT SUM(dum.tab) AS total FROM (
    SELECT COUNT(SpielerIDForderer) AS tab FROM pddb.Spiel AS b
    UNION ALL
    SELECT COUNT(SpielerIDGefordert) AS tab FROM pddb.Spiel AS a WHERE SpielerIDGefordert=SpielerIDForderer
) AS dum

我在这种情况下的预期结果是 9

Answer 1

试试这个

select id, count(*) as counting from 
(
select SpielerIDForderer as id from table
union all
select SpielerIDGefordert from table
) as t group by id

Answer 2

SELECT value, count(*) AS total FROM (
    SELECT SpielerIDForderer AS value FROM pddb.Spiel AS b
    UNION ALL
    SELECT SpielerIDGefordert AS value FROM pddb.Spiel AS a
) AS dum
group by value
order by total desc
limit 1

从拖曳列计算大多数记录

2 个答案: