1. select count(1) from (select * from Table1 union all select * from table2) T2. select sum(age) from (select * from Table1 union all select * from table2) T
用Union All 就行了 ---------------------------- 1. select count(*) As '两个表共有的条数' from ( select * from 第1个表 union all select * from 第2个表 ) T 2. select sum(age) As '总和' from ( select * from 第1个表 union all select * from 第2个表 ) T
有2个表,结构完全相同,例如:Id,Name,Age 求: 1、两个表中共有的数据条数select count(1) from table1 a,table2 b where a.id=b.id and a.name=b.name and a.age=b.age 2、两个表中所有数据的Age字段的总和select sum(age) from table1 select sum(age) from table2
select count(1)
from
(select * from Table1
union all
select * from table2) T2.
select sum(age)
from
(select * from Table1
union all
select * from table2) T
----------------------------
1.
select
count(*) As '两个表共有的条数'
from (
select * from 第1个表
union all
select * from 第2个表
) T
2.
select
sum(age) As '总和'
from (
select * from 第1个表
union all
select * from 第2个表
) T
求:
1、两个表中共有的数据条数select count(1) from table1 a,table2 b where a.id=b.id and a.name=b.name and a.age=b.age
2、两个表中所有数据的Age字段的总和select sum(age) from table1
select sum(age) from table2