SQL Server为什么关键字'select'附近的语法不正确

Question

select *
from 
    (select * 
     from 
         (select t1.stdid
         from t1) as table1
     cross join 
         select * 
         from 
             (select t2.Subid
              from t2) as table2
    ) as table3

Answer 1

Try the query below. You included an addition select * from that you should have left out.

select *
from (
 select * 
 from (
    select t1.stdid
    from t1
    ) as table1
cross join 
-- select * from : This line is extraneous and is causing your error.
   (
    select t2.Subid
    from t2
    ) as table2
) as table3

Alternatively, you will get the same result if your query was written as:

 select * 
 from (
    select t1.stdid
    from t1
    ) as table1
cross join 
   (
    select t2.Subid
    from t2
    ) as table2

Answer 2

Please don't use * in the query. Just select the column which you want.Please see below:

select ID
from 
    (select t1.id as ID
     from 
         (select t1.id
         from t1) as t1
     cross join 

             (select t2.id
              from t2) as t2
    ) as table3