-- hadoop开头的是UCenter表，cdb开头的是BBS部分的表
-- 搜索出所有垃圾用户名: select `hadoop_members`.`username` from `hadoop_members` left join `cdb_members` on `hadoop_members`.`username`=`cdb_members`.`username` where `cdb_members`.`username` is null; select `hadoop_members`.`username` from `hadoop_members` where not exists (select `cdb_members`.`username` from `cdb_members` where `hadoop_members`.`username`=`cdb_members`.`username`);
-- 搜索出垃圾用户个数: select count(`hadoop_members`.`username`) from `hadoop_members` left join `cdb_members` on `hadoop_members`.`username`=`cdb_members`.`username` where `cdb_members`.`username` is null; select count(`hadoop_members`.`username`) from `hadoop_members` where not exists (select `cdb_members`.`username` from `cdb_members` where `hadoop_members`.`username`=`cdb_members`.`username`);
-- 删除垃圾用户 delete from `hadoop_members` where not exists (select 1 from `cdb_members` where `hadoop_members`.`username`=`cdb_members`.`username`);
本文转自eyjian 51CTO博客，原文链接：/mooon/909768，如需转载请自行联系原作者
