sql求解
表a
列 a1 a2
记录 1 a
1 b
2 x
2 y
2 z
用select能选成以下结果吗?
1 ab
2 xyz 自解:select
Select a1, t1.a2from a
Join (select a1, a2 from a where a1=1) t1
On (a.a1=t1.a1)
Join (select a1, a2 from a where a1=2) t2
On (a.a1=t2.a1)
group by a1
表a
列 a1 a2
记录 1 a
1 b
2 x
2 y
2 z
用select能选成以下结果吗?
1 ab
2 xyz 自解:select
Select a1, t1.a2from a
Join (select a1, a2 from a where a1=1) t1
On (a.a1=t1.a1)
Join (select a1, a2 from a where a1=2) t2
On (a.a1=t2.a1)
group by a1
解决方案 »
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SELECT A1,REPLACE(A2,',','') A2 FROM
(
SELECT A1,WMSYS.WM_CONCAT(A2) A2, FROM A
GROUP BY A1)
用这个语句调用
select distinct a1,f_get(a1) from a
select a1,f(a1) from (select distinct a1 from a ) t