合并多个 oracle 查询以产生一个结果
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Merging multiple oracle queries to produce one result
提问by ziggy
Is it possible to execute the following query as one query?
是否可以将以下查询作为一个查询执行？
[code]
[代码]
select count(*) from tableA;
select count(*) from tableB;
select count(*) from tableC;
select count(*) from tableD;
[/code]
[/代码]
ie. the result to be something like this
IE。结果是这样的
|TablA|TableB|TableC|TableD|
|50 |300 |30 |9|
Thanks
谢谢
回答by John
select * from
(select count(*) from tableA),
(select count(*) from tableB),
(select count(*) from tableC),
(select count(*) from tableD);
回答by xkonnectDeveloper
Yes
是的
select count(*) from tableA;
union all
select count(*) from tableB;
union all
select count(*) from tableC;
union all
select count(*) from tableD;
回答by Lieven Keersmaekers
Following should work with any DBMS.
以下应该适用于任何 DBMS。
SELECT *
FROM (select count(*) as tableA from tableA) a
full outer join (select count(*) as tableB from tableB) b
full outer join (select count(*) as tableC from tableC) c
full outer join (select count(*) as tableD from tableD) d
回答by FerkiC
try this:
尝试这个：
with
one as (select count(1) as counterA, 1 as dummy from tableA),
two as (select count(1) as counterB, 1 as dummy from tableB),
three as (select count(1) as counterC, 1 as dummy from tableC),
four as (select count(1) as counterD, 1 as dummy from tableD)
用
一个作为（SELECT COUNT（1）作为counterA，1如从表A虚设），两个为（SELECT COUNT（1）作为counterB，1为从tableB的虚设），三个为（SELECT COUNT（1）作为counterC，1为来自 tableC 的虚拟），四个作为（选择 count(1) 作为 counterD，1 作为来自 tableD 的虚拟）
select one.counterA, two.counterB, three.counterC, four.counterD from one, two, three, four where one.dummy = two.dummy and two.dummy = three.dummy and three.dummy = four.dummy;
从一、二、三、四中选择 one.counterA、two.counterB、three.counterC、four.counterD，其中 one.dummy = two.dummy 和 two.dummy =three.dummy 和three.dummy =four.dummy；
