sql - 查询执行问题

Question

我有一个像这样的查询

select user_id ,'abc' as  user_name from t_user where user_refId=123 

，我想在这里再添加一个子句，例如

select user_id ,
'abc' as  user_name
select count(user) from users as user_num
 from t_user where user_refId=123 

这行不通。

Answer 1

select user_id,
      'abc' as user_name, 
       (select count(user) from users)  as user_num
from t_user 
where user_refId=123 

Answer 2

请将'abc' as user_nameandselect count(user) from users as user_num语句分开，","并将第二个语句放在括号中，如(select count(user) from users) as user_num.

      select user_id,
      'abc' as user_name, 
       (select count(user) from users)  as user_num
       from t_user where user_refId=123;