create table test
(
id int primary key,
username varchar(20),
pwd varchar(20)
)
insert into test values(1,'a','b')
insert into test values(2,'a','c')
insert into test values(3,'a','d')
delete test from test t where exists (select 1 from test where T.id<id and T.username=username)
(
id int primary key,
username varchar(20),
pwd varchar(20)
)
insert into test values(1,'a','b')
insert into test values(2,'a','c')
insert into test values(3,'a','d')
delete test from test t where exists (select 1 from test where T.id<id and T.username=username)
根据你的要求,你应该用ID或是PWD
--delete here
set rowcount 0 set rowcount N
可以设置每次影响的行数只为N行
如果N=0,表示恢复正常。---------------------------------------
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