求个SQL语句或效率稍高一点的其它解决方案,我脑子转不过弯(MySQL))
菜亲虫 2011-12-18 03:50:18 现有两张表,用与处理消息中心消息会话。
message_sessions,是消息会话,其中包括该消息会话中包含的成员,对应于message_session_members表,外键session_id引用message_sessions.id。
现想求一SQL语句,查询一个消息会话中包含的成员和我传入的几个ID是否一致,并且数量也要一致。
比如message_sessions.id=1时,该会话有三个成员57,58,59,那么当我传入的id是57,58,59时才列出结果,当传入的id是57,58或57,58,59,60时,不列出结果
create table `message_sessions` (
`id` int ,
`message_count` int ,
`member_count` int
);
insert into `message_sessions` (`id`, `message_count`, `member_count`) values('1','0','2');
insert into `message_sessions` (`id`, `message_count`, `member_count`) values('2','0','3');
insert into `message_sessions` (`id`, `message_count`, `member_count`) values('3','0','2');
insert into `message_sessions` (`id`, `message_count`, `member_count`) values('4','0','2');
create table `message_session_members` (
`session_id` int,
`user_id` int
);
insert into `message_session_members` (`session_id`, `user_id`) values('1','57');
insert into `message_session_members` (`session_id`, `user_id`) values('1','58');
insert into `message_session_members` (`session_id`, `user_id`) values('1','59');
insert into `message_session_members` (`session_id`, `user_id`) values('2','57');
insert into `message_session_members` (`session_id`, `user_id`) values('2','120');
insert into `message_session_members` (`session_id`, `user_id`) values('2','121');
insert into `message_session_members` (`session_id`, `user_id`) values('3','58');
insert into `message_session_members` (`session_id`, `user_id`) values('3','59');
insert into `message_session_members` (`session_id`, `user_id`) values('4','57');
insert into `message_session_members` (`session_id`, `user_id`) values('4','58');