How do I consolidate these two subqueries? - mysql

Question

I am writing an e-commerce query that polls for users with specific roles. The exact purpose of the query isn't important, all that matters is that it's working as intended right now. However, I really would like to clean up this section of the query
.
.
.
where u.firstname is not null
and u.users_id in (
select u.users_id from users u
inner join mbrrole mr on mr.member_id = u.users_id and mr.ORGENTITY_ID IN (
select ORGENTITY_ID from po_org_tree_v
)
inner join roledesc rd on rd.role_id = mr.role_id
where 1=1
and rd.displayname IN ('Customer Service Representative', 'Account Representative')
)
and u.users_id in (
select u.users_id from users u
inner join mbrrole mr on mr.member_id = u.users_id and mr.ORGENTITY_ID IN (
select ORGENTITY_ID from po_org_tree_v
)
inner join roledesc rd on rd.role_id = mr.role_id
where 1=1
and rd.displayname = 'Registered Customer'
);
As you can see, I have to nearly identical subqueries in the parent query's where clauses, where the only difference between then is the rd.displayname check. Is there some way in sql to comine two like queries into a "function", similar to actual functions in programming languages? How can I combine these subqueries to clean up the main query?

Answer 1

The code is checking that two different types of roles are available for each user.
Your current method might have the best performance, but you can simplify this down to one subquery:
where u.firstname is not null and
u.users_id in (select mr.member_id
from mbrrole mr inner join
roledesc rd
on rd.role_id = mr.role_id
where mr.ORGENTITY_ID IN (select ORGENTITY_ID from po_org_tree_v) and
rd.displayname IN ('Registered Customer', 'Customer Service Representative', 'Account Representative')
group by mr.member_id
having sum(rd.displayname = 'Registered Customer') > 0 and
sum(rd.displayname IN ('Customer Service Representative', 'Account Representative')) > 0
)
Note the following changes:
Removed users from the subquery. It is not needed.
Moved the ORGENTITY_ID condition to the where clause.
Added the GROUP BY and HAVING. The HAVING checks that both types of roles are defined for the user.

Answer 2

You can use this link (https://dev.mysql.com/doc/refman/5.7/en/create-procedure.html) to help you!
You'll need to use a procedure and not a function to return a result set so something like this should work (MySql is not my cup of tea):
CREATE PROCEDURE
procedureName(s String)
BEGIN
SELECT u.users_id
FROM users u
INNER JOIN mbrrole mr ON mr.member_id = u.users_id AND mr.ORGENTITY_ID
IN (
SELECT ORGENTITY_ID FROM po_org_tree_v
)
INNER JOIN roledesc rd ON rd.role_id = mr.role_id
WHERE rd.displayname = s;
END
And you call this procedure like this :
WHERE u.firstname IS NOT NULL
AND (u.users_id in procedureName('Customer Service Representative')
OR u.users_id in procedureName('Account Representative'))
AND u.users_id in procedureName('Registered Customer');