IF EXISTS(SELECT * FROM member) insert into member(M_ID,M_pwd,M_email) values('luias','355129','') insert 怎么能用WHERE. 严重错误.
IF EXISTS(SELECT * FROM member WHERE M_ID='luias') insert into member(M_ID,M_pwd,M_email) values('luias','355129','')
樓上寫的有些問題.有兩種寫法: 1. If Not Exists(Select M_ID from member Where M_ID = 'liu') insert into member(M_ID,M_pwd,M_email) values('liu','123456','')2. insert into member(M_ID,M_pwd,M_email) Select 'liu','123456','' Where Not Exists (Select M_ID from member Where M_ID = 'liu')
insert into member(M_ID,M_pwd,M_email) values('luias','355129','') insert 怎么能用WHERE. 严重错误.
insert into member(M_ID,M_pwd,M_email) values('luias','355129','')
1.
If Not Exists(Select M_ID from member Where M_ID = 'liu')
insert into member(M_ID,M_pwd,M_email) values('liu','123456','')2.
insert into member(M_ID,M_pwd,M_email) Select 'liu','123456',''
Where Not Exists (Select M_ID from member Where M_ID = 'liu')