table test:
t_name id flag
aaa 1 1
aaa 2 1
aaa 3 0
aaa 4 0
更新flag=0
条件:t_name='aaa',flag=0,min(id)
结果:
aaa 1 1
aaa 2 1
aaa 3 1
aaa 4 0
t_name id flag
aaa 1 1
aaa 2 1
aaa 3 0
aaa 4 0
更新flag=0
条件:t_name='aaa',flag=0,min(id)
结果:
aaa 1 1
aaa 2 1
aaa 3 1
aaa 4 0
where id in (select min(id) from test where t_name='aaa' and flag=0)
update test set flag=1 where id=( select min(id) from test where name='aaa' and flag=0)