with t1 as
(
select Username, product_id
from tablename
where product_id = 363
group by Username, product_id
),
t2 as
(
select Username, product_id
from tablename
where product_id = 365
group by Username, product_id
)
select Username 
from t1
where Username in
(select Username 
from t2)

------解决方案--------------------
SQL code
SELECT * FROM TB T 
WHERE EXISTS(SELECT 1 FROM TB WHERE username=T.username  AND product_id=363) AND 
 EXISTS(SELECT 1 FROM TB WHERE username=T.username  AND product_id=365)

------解决方案--------------------
SQL code
select
 * 
from 
 tb 
where
 username in(select username from tb group by username having count(1)=2) 
and
 product_id in('363','365')

------解决方案--------------------
select * from tb a,
(SELECT username  FROM TB WHERE product_id=363) b
(SELECT username  FROM TB WHERE product_id=365) c
where b.username=c.username and a.username=c.username

------解决方案--------------------
SELECT * FROM TB T  
WHERE EXISTS(SELECT 1 FROM TB WHERE username=T.username  AND product_id=363) AND  
  EXISTS(SELECT 1 FROM TB WHERE username=T.username  AND product_id=365)
AND T.product_id IN(365,363)

--把product_id 单独一个索引
username 单独一个
先试试看。索引有没有效有作用还要看你的数据量。数据结构这些
语句按上面的。


------解决方案--------------------
探讨

引用:

SELECT * FROM TB T
WHERE EXISTS(SELECT 1 FROM TB WHERE username=T.username AND product_id=363) AND
EXISTS(SELECT 1 FROM TB WHERE username=T.username AND product_id=365)
AND T.produc……


------解决方案--------------------
你查询363,365多少数据量?
username include(product_id)再试试

+1

------解决方案--------------------
SELECT distinct username FROM TB  
试试这个语句有多少数据