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Jetbrains全系列IDE稳定放心使用
set names utf8;
select catid from supe_categories where name=’金融’;
得出catid;
create table multmp select * from supe_spaceitems where catid in(select catid from supe_categories where name=’金融’); 假设上一句的出的catid为1
／／以下语句是过滤重复
create table tmpa as select itemid from multmp where subject in(select subject from multmp group by subject having count(itemid)>1);
create table tmpb as select min(itemid) as itemid from multmp group by subject having count(itemid)>1;
create table tmptmp as select itemid from multmp where itemid in (select itemid from tmpa ) and itemid not in (select itemid from tmpb);//要删除的数据的itemid
delete from supe_spacenews where itemid in (select itemid from tmptmp);//删除news
delete from multmp where itemid in (select itemid from tmptmp);
drop table tmpa;
drop table tmpb;
drop table tmptmp;
delete from supe_spaceitems where catid in (select catid from supe_categories where name=’金融’); ／／删除原表中 catid为1的数据
insert into supe_spaceitems select * from multmp; ／／将过滤后的数据 添会原表
drop table multmp;／／删除中间表
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