ALL、SOME 和 ANY是SQL Server 三个比较运算符，其中 SOME 和 ANY 是等效的
SOME 或 ANY：当表达式与子查询返回的至少一个值比较时满足比较条件， SOME 或 ANY 就返回 TRUE。否则返回 FALSE
ALL ：当表达式与子查询返回的所有值比较时满足比较条件， ALL 就返回 TRUE。否则返回 FALSE
- create table test01 ( num int)
-
- insert into test01
- select 5 union
- select 6
-
- create table test02 (num int)
-
- insert into test02
- select 2 union
- select 3 union
- select 6 union
- select 7
-
- select * from test01
- select * from test02
至此 test01 表中有数据： 5和 6 ， test02表中有数据 ：2,3,6,7
- select num as num1 from test02 where num > all(select num from test01 )
- select num as num2 from test02 where num > any(select num from test01 )
- select num as num3 from test02 where num > some(select num from test01)
- select num as num4 from test02 where num = all (select num from test01 )
- select num as num5 from test02 where num = any(select num from test01 )
- select num as num6 from test02 where num = some(select num from test01)
- select num as num7 from test02 where num <> all (select num from test01 )
- select num as num8 from test02 where num <> any (select num from test01 )
- select num as num9 from test02 where num <>some(select num from test01)
从上面的测试结果看，= any 或 = some 与平时使用的 in 是等效的。
