SQL query needed for a complex structure - mysql

Question

I have a tricky SQL query that needs to be built to get the highest priority rule based on customer session and geo IP data.
I attached the following tables: rule, rule_attribute, rule_attribute_value.
rule - table where all rules are stored
Click here to see a screenshot of the 'rule' table
rule_attribute - table where all rule attributes are stored
Click here to see a screenshot of the 'rule_attribute' table
rule_attribute_value - table where all rule attribute values are stored
Click here to see a screenshot of the 'rule_attribute_value' table
When the customer logs in, I have access to all those attributes (customer_id, customer_group_id, country_id, subdivision_one_id, subdivision_two_id). Only customer_id and customer_group_id will always have values. The others are optional, but there is a dependency between them. We can't have subdivisions without selecting first a country. We can have a second subdivision without selecting a country and then the first subdivision.
What I would like to get is the highest priority rule that matches the session data in the most optimized way. I have a solution that involves some coding, but I want to see if it's possible directly through SQL.
Here are some examples of session data arrays:
Array
(
[customer_id] => 2
[customer_group_id] => 1
[current_store_id] => 0
[country_id] => 15
[subdivision_one_id] => 224
[subdivision_two_id] =>
)
Array
(
[customer_id] => 2
[customer_group_id] => 1
[current_store_id] => 0
[country_id] => 15
[subdivision_one_id] =>
[subdivision_two_id] =>
)
Array
(
[customer_id] => 3
[customer_group_id] => 2
[current_store_id] => 0
[country_id] =>
[subdivision_one_id] =>
[subdivision_two_id] =>
)

Answer 1

Without a better understanding of the rules and data this is the best I can come up with. It is based on your first array example -
SELECT `r`.*
FROM `rule_attribute_value` `rav`
INNER JOIN `rule` `r`
ON `rav`.`rule_id` = `r`.`rule_id`
INNER JOIN `rule_attribute` `ra`
ON `rav`.`attribute_id` = `ra`.`attribute_id`
WHERE
(`rav`.`store_id` = 0 AND `ra`.`attribute_code` = 'customer' AND `rav`.`value` = 2) OR
(`rav`.`store_id` = 0 AND `ra`.`attribute_code` = 'customer_group' AND `rav`.`value` = 1) OR
(`rav`.`store_id` = 0 AND `ra`.`attribute_code` = 'country' AND `rav`.`value` = 15) OR
(`rav`.`store_id` = 0 AND `ra`.`attribute_code` = 'subdivision_one' AND `rav`.`value` = 224)
GROUP BY `r`.`rule_id`
HAVING COUNT(DISTINCT `rav`.`attribute_id`) = 4 /* 4 IS THE NUMBER OF ATTRIBUTES BEING QUERIED */
ORDER BY `r`.`position` ASC
LIMIT 1;