I have a table with some ids + titles. I want to make the title column unique, but it has over 600k records already, some of which are duplicates (sometimes several dozen ti
This shows how to do it in SQL2000. I'm not completely familiar with MySQL syntax but I'm sure there's something comparable
create table #titles (iid int identity (1, 1), title varchar(200))
-- Repeat this step many times to create duplicates
insert into #titles(title) values ('bob')
insert into #titles(title) values ('bob1')
insert into #titles(title) values ('bob2')
insert into #titles(title) values ('bob3')
insert into #titles(title) values ('bob4')
DELETE T FROM
#titles T left join
(
select title, min(iid) as minid from #titles group by title
) D on T.title = D.title and T.iid = D.minid
WHERE D.minid is null
Select * FROM #titles