mysql - Multi-conditional join -


i bet easy question mysql chops bit rusty. need little generating proper query following scenario multi conditional join. have 1 table attributes (think tags) , table have list of records. running problems when want match page has more 1 attribute defined in query.

+--------------------------------------+ | attributes                           | +-----------+------------+-------------+ | name      | value      | page_id     | +-----------+------------+-------------+ | type        food         2           |   | fruit       apple        2           |   | color       green        2           | | type        frog         3           |   | color       green        3           | +--------------------------------------+   +--------------------------------------+ | pages                                | +--------------+-----------------------+ | page_id      | title                 | +--------------+-----------------------+ | 2              granny smith          |   | 3              kermit frog       | +--------------------------------------+

use cases

query: type+food results: granny smith  query: color+green results: granny smith, kermit frog  query: type+food , color+green results: granny smith

this query playing with, not working:

select page.page_id, page.title  page_attributes  left join page on (page_attributes.page_id = page.page_id)  (page_attributes.name = 'color'  , page_attributes.value = 'green')  , (page_attributes.name = 'type'  , page_attributes.value = 'food')

along same lines nitro has, keep criteria attributes on clause. also, make sure have index on attributes table on ( page_id, name, value ) joins optimized.

select        page.page_id,        page.title            page           inner join page_attributes a1             on page.page_id = a1.page_id            , a1.name = 'color'            , a1.value = 'green'           inner join page_attributes a2            on page.page_id = a2.page_id            , a2.name = 'type'            , a2.value = 'food'     limit 10

as can see, want add "criteria", copy/past entire join. either finds match , allows include, or doesn't , ignores page record.


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