sql - how to fetch this data in one query? -

i want fetch data in simple query

i use

select user_id , order_id  product  order_id = 3  group user_id , order_id ;  

but result 1 row group

example input:

#user_id  #order_id 1         2 1         3 2         3 2         4 3         1 3         4 3         5 4         1 4         3 4         12 4         6 5         4 

where order_id = 4 then

output :

#user_id  #order_id  2         3 2         **4** 3         1 3         **4** 3         5 5         **4** 

try this:

select p2.user_id, p2.order_id  product p1 inner join product p2 on p1.userid = p2.userid p1.order_id = 4 

this should effective way data. if slow you, should create proper indexes on product table.

also note work specifying 1 single order_id, need adjustments more order_ids (distinct, specific) , bigger difference selecting userid.