delete duplicate record in SQL server

create table empp(id int identity ,name varchar(30))

insert into empp values('bhanu')

select * from empp

-- for selecting duplicate record

select name ,count(*)  cnt from empp e group by e.name having count(*) >1

-- for selecting non-duplicate record

select name ,count(*)  cnt from empp e group by e.name having count(*) =1

• 
  

--with having

delete from empp  where id  in (select max(id) from empp  group by name having count(*)>1)

--without having

delete from empp  where id not in (select max(id) from empp  group by name)

DELETE FROM emp WHERE ID NOT IN (SELECT MIN(ID) FROM emp GROUP BY FName)

delete from tableName where UniqueColumn NOT IN (select MIN(UniqueColumn) from tableName GROUP BY DuplicateRecoedColumn/DeletedDuplicateColumn)