query - sql server delete duplicate rows but keep one

Ayuda de eliminación de SQL Query Duplicate

Question

Necesito eliminar registros semi duplicados de la siguiente tabla

ID PID SCORE
1 1 50
2 33 20
3 1 90
4 5 55
5 7 11
6 22 34

Para cualquier PID duplicado que exista, quiero eliminar el registro de menor puntaje. En el ejemplo anterior, ID 1 sería eliminado. Intento encontrar una forma de hacerlo sin usar bucles pero realmente estoy luchando.

Cualquier ayuda sería apreciada.

Gracias

Answer 1

No puedo ver tu consulta, así que hice este ejemplo ...

SELECT
PID,
MAX(Score)
FROM
tblTable
GROUP BY
PID

Answer 2

prueba esto..

 declare @tt table(id int, pid int,score int)
insert into @tt
select 1,1,50 union all
select 2,33,50 union all
select 8,33,80 union all
select 3,1,90 union all
select 4,5,50 union all
select 5,5,10 union all
select 6,6,10 union all
select 7,6,50
---------
delete from @tt where id in (
select t1.id from @tt t1 inner join
(
select MIN(score) tScore,pid tPid from @tt where pid in
(select pid from @tt group by pid having count (pid) > 1) group by pid
) t2 on t1.pid=t2.tPid and t1.score=t2.tScore)
select * from @tt

Answer 3

WITH q AS
(
SELECT *, ROW_NUMBER() OVER (PARTITION BY pid ORDER BY score) AS rn
FROM mytable
)
DELETE
FROM q
WHERE rn = 1

Para dejar los resultados que no tienen duplicados:

WITH q AS
(
SELECT *,
ROW_NUMBER() OVER (PARTITION BY pid ORDER BY score) AS rn,
COUNT(*) OVER (PARTITION BY pid) AS cnt
FROM mytable
)
DELETE
FROM q
WHERE rn = 1
AND cnt > 1

Answer 4

 DELETE t.*
FROM Table1 t
JOIN (SELECT pid, MIN(score) minScore, MAX(id) maxId
FROM Table1
GROUP BY pid) t1
ON t.pid = t1.pid
AND t.score = t1.minScore
AND t.id < t1.maxId