How to get multiple conditions in m:n relations with multiple joins? - mysql

Question

I have to write a complex query to get products in MySQL with multiple conditions and stucking on relations with multiple conditions.
The database structure is built from Typo3. At the moment I have 4 joins with multiple conditions. Everything is working fine but the last line of my SQL is the problem. But I can't get any solution.
SELECT p.uid
FROM tx_myext_domain_model_product p
JOIN tx_myext_domain_model_productwirkung w
ON p.uid = w.product
JOIN sys_category_record_mm ck
ON p.uid = ck.uid_foreign
JOIN sys_category_record_mm cc
ON p.uid = cc.uid_foreign
JOIN sys_category_record_mm cw
ON w.uid = cw.uid_foreign
WHERE p.season IN(1,'')
AND p.type = "herbizid"
AND ck.uid_local = 2
AND ck.tablenames = "tx_myext_domain_model_product"
AND ck.fieldname = "culture"
AND cc.tablenames = "tx_myext_domain_model_product"
AND cc.fieldname = "chemicals"
AND cw.tablenames = "tx_myext_domain_model_productwirkung"
AND cw.uid_local IN (2, 395, 257)
AND w.grad = 6;
# and wirkung with cw.uid_local = 2 should have w.grad = 6
# and wirkung with cw.uid_local = 395 should have w.grad = 6
# and wirkung with cw.uid_local = 257 should have w.grad in range from 1 to 6
The 'productwirkung' should have the category 2, 395 and 257 and the 'productwirkung' with the category 2 and 395 should have the grad 6.
I know, with this last line I can't get anything...
EDIT
I cannot add w.grad = 6 because the product should have a productwirkung with the category 257 too with grad 1 - 6. One product has multiple relations with productwirkung. So if there is a product with productwirkung 2 with grad = 6, productwirkung 395 with grad = 6 and productwirkung 257 with grad = 3 I want this product. If I ask for ... cw.uid_local IN (2, 395, 257) AND w.grad = 6 The product wont be selected because productwirkung 257 doesn't has w.grad = 6.

Answer 1

Assuming uid_local is unique, it can not by definition be both 2 and 395
I guess you wanted to go for
...
AND ((`cw`.`uid_local` = 2 AND `w`.`grad` = 6) OR (`cw`.`uid_local` = 395 AND `w`.`grad` = 6));
EDIT
Since in both sub-expressions you're checking for w.grad = 6 this might also be simplified into
...
AND w.grad = 6
AND (cw.uid_local = 2 OR cw.uid_local = 395)
Or even further simplified into
...
AND w.grad = 6
AND cw.uid_local IN (2, 395)

Answer 2

Your problem is that your last two where conditions are conflicting. They state that a row has to contain the cw.uid_local of either 2, 395 or 257 AND must have the ID 2 AND 395 in a single row. If you rewrite the last two lines as an OR conditional, you should get the results you're looking for:
SELECT `p`.`uid`
FROM `tx_myext_domain_model_product` `p`
INNER JOIN `tx_myext_domain_model_productwirkung` `w`
ON `p`.`uid` = w.product
INNER JOIN `sys_category_record_mm` `ck`
ON `ck`.`tablenames` = "tx_myest_domain_model_product"
AND `p`.`uid` = ck.uid_foreign
AND `ck`.`fieldname` = "culture"
INNER JOIN `sys_category_record_mm` `cc`
ON `cc`.`tablenames` = "tx_myext_domain_model_product"
AND `p`.`uid` = cc.uid_foreign
AND `cc`.`fieldname` = "chemicals"
INNER JOIN `sys_category_record_mm` `cw`
ON `cw`.`tablenames` = "tx_myext_domain_model_productwirkung"
AND `w`.`uid` = cw.uid_foreign
WHERE ((`p`.`season` = "1") OR (`p`.`season` = ""))
AND (`p`.`type` = "herbizid")
AND (`ck`.`uid_local` = "2")
AND ((`cw`.`uid_local` IN (2, 395) AND `w`.`grad` = 6) OR `cw`.`uid_local` = 257);
EDIT
Upon reading your edit, I think you'd best be served with subqueries, seeing as your required conditions are conflicting for a single query.
If you want the products where ALL conditions are met (products with "children" that have a (uid_local of 2 AND grad of 6) AND "children" with (uid_local of 395 AND grad of 6) AND "children" with (uid_local of 257 AND grad between 1 and 6)), I would suggest using inner joins with subqueries to constrict your data to the "child cases":
SELECT DISTINCT p.uid
FROM tx_myext_domain_model_product p
### WHERE cw.uid_local = 2 AND w.grad = 6
JOIN (
SELECT p_1.uid
FROM tx_myext_domain_model_product p_1
JOIN tx_myext_domain_model_productwirkung w_1
ON p_1.uid = w_1.product
JOIN sys_category_record_mm cw_1
ON w_1.uid = cw_1.uid_foreign
WHERE cw_1.tablenames = "tx_myext_domain_model_productwirkung"
AND cw_1.uid_local = 2
AND w_1.grad = 6
) p1 ON p1.uid = p.uid
### WHERE cw.uid_local = 395 AND w.grad = 6
JOIN (
SELECT p_2.uid
FROM tx_myext_domain_model_product p_2
JOIN tx_myext_domain_model_productwirkung w_2
ON p_2.uid = w_2.product
JOIN sys_category_record_mm cw_2
ON w_2.uid = cw_2.uid_foreign
WHERE cw_2.tablenames = "tx_myext_domain_model_productwirkung"
AND cw_2.uid_local = 395
AND w_2.grad = 6
) p2 ON p2.uid = p.uid
### WHERE cw.uid_local = 257 AND w.grad BETWEEN 1 AND 6
JOIN (
SELECT p_3.uid
FROM tx_myext_domain_model_product p_3
JOIN tx_myext_domain_model_productwirkung w_3
ON p_3.uid = w_3.product
JOIN sys_category_record_mm cw_3
ON w_3.uid = cw_3.uid_foreign
WHERE cw_3.tablenames = "tx_myext_domain_model_productwirkung"
AND cw_3.uid_local = 257
AND w_3.grad BETWEEN 1 AND 6
) p3 ON p3.uid = p.uid
JOIN tx_myext_domain_model_productwirkung w
ON p.uid = w.product
JOIN sys_category_record_mm ck
ON p.uid = ck.uid_foreign
JOIN sys_category_record_mm cc
ON p.uid = cc.uid_foreign
JOIN sys_category_record_mm cw
ON w.uid = cw.uid_foreign
WHERE p.season IN(1,'')
AND p.type = "herbizid"
AND ck.uid_local = 2
AND ck.tablenames = "tx_myest_domain_model_product"
AND ck.fieldname = "culture"
AND cc.tablenames = "tx_myext_domain_model_product"
AND cc.fieldname = "chemicals";

Answer 3

If we rewrite your query, we get (amongst other things) the following:
AND cw.uid_local = 2
AND cw.uid_local = 395
Unless uid_local occupies some sort of quantum state, this is unlikely to be successful.
FWIW, I find this (slightly) easier to read...
SELECT p.uid
FROM tx_myext_domain_model_product p
JOIN tx_myext_domain_model_productwirkung w
ON p.uid = w.product
JOIN sys_category_record_mm ck
ON p.uid = ck.uid_foreign
JOIN sys_category_record_mm cc
ON p.uid = cc.uid_foreign
JOIN sys_category_record_mm cw
ON w.uid = cw.uid_foreign
WHERE p.season IN(1,'')
AND p.type = "herbizid"
AND ck.uid_local = 2
AND ck.tablenames = "tx_myest_domain_model_product"
AND ck.fieldname = "culture"
AND cw.uid_local IN (2, 395, 257)
AND cw.tablenames = "tx_myext_domain_model_productwirkung"
AND cc.tablenames = "tx_myext_domain_model_product"
AND cc.fieldname = "chemicals"
AND w.grad = 6;