写数据库语句遇到问题

[yuanfnadi]

表有两列
a b
1 2
1 3
2 3
2 1
2 2


现在要求出所有的数字一共出出现了几列
结果应该是
1 3
2 4
3 3

用数据库写我想到的方法是分别求出两列个数，相加以后减去相同的个数

[yejinmo]

结果应该是
1 3
2 5
3 3
吧

[xxoxx]

目测了一下，结果应该是
1 3
2 5
3 2

[yejinmo]

select a, count(a) from
(
(select a from test union all select b from test) as temp
)
group by a;

[yejinmo]

@yejinmo
1 3
2 5
3 2

[yuanfnadi]

重复的不算
应该是
13
24
32

33 是手抖了

[akira]

SELECT a, SUM(`t`) `count`
FROM
(
SELECT a, COUNT(a) `t`
FROM test
GROUP BY a UNION
SELECT b, COUNT(b)
FROM test
WHERE a<>b
GROUP BY b
)tt
GROUP BY a

[zeraba]

就按照你的思路 把 a b 先并到一起 参考 3 楼 一样的随便取一个 最后 group by
伪代码
select case when a = b then a else a end hebing from test
union
select case when a <> b then b end hebing

[SuperMild]

select a, sum(num) as 'count' from
(select a, count(a) as num from AandB where a <> b group by a
union all
select b, count(b) from AandB where a <> b group by b
union all
select b, count(b) from AandB where a = b group by b)
group by a;