insert into friends (user_id1,user_id2)
select user_id from user where UserName='summer'or UserName='winter'
这给出了一个错误。我想将'summer'的user_id插入user_id1,将'winter'的user_id插入user_id2。请帮帮忙?
答案 0 :(得分:0)
insert into friends (user_id1,user_id2)
select user_id, -1 from user where UserName='summer'
update friends
set user_id2 = (select user_id from user where UserName='winter')
where user_id2 = -1
答案 1 :(得分:0)
Select必须具有与insert相同的列数,因此:
INSERT INTO friends (user_id1,user_id2)
SELECT (SELECT user_id FROM user where UserName='Summer') AS user_id1, (SELECT user_id FROM user WHERE UserName='Winter') AS user_id2
应该做的伎俩
答案 2 :(得分:0)
INSERT INTO table2 (user_id1,user_id2)
SELECT
(SELECT UserName
FROM table1
WHERE UserName='Summer') AS user_id1,
(SELECT UserName
FROM table1
WHERE UserName='Winter') AS user_id2