我有两组结果:
SELECT name, count(appearance) as countA from table where results = '1'
SELECT name, count(appearance) as countB from table where results = '2'
我希望将它们并排组合,如下所示:
+---------+---------+---------+
| col_1 | countA | countB |
+---------+---------+---------+
| John | 3 | 1 |
| Mary | 1 | 2 |
| Gary | 2 | NULL |
| Sean | 4 | NULL |
| Mike | NULL | 6 |
+---------+---------+---------+
我该怎么做?
答案 0 :(得分:5)
这应该(在Oracle中)而不需要自联接
SELECT name
, sum( case results when '1' then 1 else 0 end ) as countA
, sum( case results when '2' then 1 else 0 end ) as countB
from table
where results IN ( '1', '2' )
group by
name
答案 1 :(得分:1)
您可以按如下方式使用自我加入
select a.col_1, a.countA, b.countB from table a, table b
where a.col_1 = b.col_1 and a.results='1' and b.results='2'
答案 2 :(得分:-1)
SELECT name, count(appearance) as countA, null AS countB from table where results = '1'
UNION ALL
SELECT name, null AS countA, count(appearance) as countB from table where results = '2'
答案 3 :(得分:-1)
SELECT `table`.name, countA, countB
FROM tab
LEFT OUTER JOIN
(SELECT name, count(appearance) as countA from `table` where result = '1' group by name) as tmp1
ON `table`.name = tmp1.name
LEFT OUTER JOIN
(SELECT name, count(appearance) as countB from `table` where result = '2' group by name) as tmp2
ON `table`.name = tmp2.name;