Just can't seem to get mysql query correct - mysql

Question

I am trying to get results that i know are there but just can't seem to get the query right. I am using the following:
SELECT
*
FROM
carpets AS c
INNER JOIN carpet_relations AS r ON c.id = r.carpet_id
WHERE
c.active = '1'
AND **((r.relation_type = '5')
AND (r.related_id = '1' ))**
*AND* ((r.relation_type = '4')
AND (r.related_id = '1'))
AND (c.width_feet BETWEEN '0' AND '17')
AND (c.width_inches BETWEEN '0' AND '11')
AND (c.height_feet BETWEEN '0' AND '29')
AND (c.height_inches BETWEEN '0' AND '11')
ORDER BY
c.item_no
as you can see i am trying get results that have two matching fields in a second table if i change the and that is in italics to an or i get results but it is results for both i need the results that are in the set prior to the and which is bold
so it would be something like:
list that has relation type 5 and 4
keep in mind that related id could be different for both there are three colums carpet_id,related_id,relation_type
thanks for any help
c_categories
Column Type Null Default Comments
id int(11) No
title varchar(250) No
active int(11) No
weight int(11) No
template_id int(11) No
c_sizes
Column Type Null Default Comments
id int(11) No
title varchar(250) No
active int(11) No
weight int(11) No
template_id int(11) No
carpet_relations
Column Type Null Default Comments
carpet_id int(11) No <------ signifies which carpet the relationship is with
related_id int(11) No <------ the id of the c_size or c_categories to use
relation_type int(11) No <------ signifies which table either c_sizes or c_categories

Answer 1

Change this:
((r.relation_type = '5') AND (r.related_id = '1' )) AND ((r.relation_type = '4') AND (r.related_id = '1'))
to this:
(r.relation_type = '5' OR r.relation_type = '4') AND (r.related_id = '1')

Answer 2

For flexibility's sake:
r.relation_type IN (4, 5)

Answer 3

Now I think I understand your problem - you're after the intersection of results of type 5 and type 4.
This could be done in PHP as you mention by doing two queries and intersecting them, or you can do this in MySQL by joining the carpet_relations table on twice like so:
SELECT
*
FROM
carpets AS c
INNER JOIN carpet_relations AS r1 ON c.id = r1.carpet_id
INNER JOIN carpet_relations AS r2 ON c.id = r2.carpet_id
WHERE
c.active = '1'
AND (r1.relation_type = '5')
AND (r1.related_id = '1' )
AND (r2.relation_type = '4')
AND (r2.related_id = '1')
AND (c.width_feet BETWEEN '0' AND '17')
AND (c.width_inches BETWEEN '0' AND '11')
AND (c.height_feet BETWEEN '0' AND '29')
AND (c.height_inches BETWEEN '0' AND '11')
ORDER BY
c.item_no

Answer 4

AND ((r.relation_type = '5')
AND ((r.relation_type = '4')
you are expecting relation type to be 5 and 4 at the same time.
Would you like to have some "or" in your salad?
edit:
SELECT
*
FROM
carpets AS c
INNER JOIN carpet_relations AS r ON c.id = r.carpet_id
WHERE
c.active = '1'
AND
((r.relation_type = '5') AND (r.related_id = '1' ))
OR
((r.relation_type = '4') AND (r.related_id = '1'))
AND (c.width_feet BETWEEN '0' AND '17')
AND (c.width_inches BETWEEN '0' AND '11')
AND (c.height_feet BETWEEN '0' AND '29')
AND (c.height_inches BETWEEN '0' AND '11')
ORDER BY
c.item_no
solves your problem.