select emp_name as A from emp where A = 'S0207069' 不行。 select emp_name as A from emp where emp_name = 'S0207069' 可以的。 select emp_name as A from emp order by A 可以。
select * from (select emp_name as A from) emp where A = 'S0207069'
select中指定的别名不能直接用在where中,这个和access不同.可以用这种方法用 select (select emp_name as A from emp) a where A = 'S0207069'或: select emp_name as A from emp where emp_name = 'S0207069'
select * from (select emp_name as A from emp) tem where A= 'S0207069'
select emp_name as A from emp where A = 'S0207069' 不行。 select emp_name as A from emp where emp_name = 'S0207069' 可以的。 select emp_name as A from emp order by A 可以。
select emp_name as A from emp where emp_name = 'S0207069' 可以的。
select emp_name as A from emp order by A 可以。
select (select emp_name as A from emp) a where A = 'S0207069'或:
select emp_name as A from emp where emp_name = 'S0207069'
select emp_name as A from emp where emp_name = 'S0207069' 可以的。
select emp_name as A from emp order by A 可以。