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POMySql: make this query faster… is there a way ? PART TWO
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copied!<p>This is part two of the question: <a href="https://stackoverflow.com/questions/2913639/mysql-make-this-query-faster-theres-a-way">MySql: make this query faster... is there a way?</a></p> <p>this query still run slowly:</p> <pre><code>SELECT b.id, b.name, c.name FROM bookcorr as a JOIN books as b on b.id = a.books_id = JOIN Library as c on c.id = a.library_id WHERE a.category_id = '2521' AND a.library_id = '4983' ORDER BY b.name ASC LIMIT 0,15 </code></pre> <p>Any suggest ?</p> <pre><code>CREATE TABLE `bookcorr` ( `category_id` smallint(4) unsigned NOT NULL, `book_id` mediumint(7) unsigned NOT NULL, `library_id` smallint(5) unsigned NOT NULL, UNIQUE KEY `cat_id_3` (`category_id`,`book_id`,`library_id`), KEY `category_id` (`category_id`), KEY `book_id` (`book_id`), KEY `library_id` (`library_id`), KEY `cat_id_2` (`cat_id`,`com_id`)) CREATE TABLE `books` ( `id` mediumint(7) unsigned NOT NULL AUTO_INCREMENT, `com_id` smallint(5) unsigned NOT NULL, `name` varchar(256) NOT NULL, .... PRIMARY KEY (`id`), KEY `name` (`name`), FULLTEXT KEY `search` (`name`,`author`) ) CREATE TABLE `Library` ( `id` smallint(4) unsigned NOT NULL AUTO_INCREMENT, `name` varchar(256) NOT NULL, ... UNIQUE KEY `id` (`id`), KEY `library_name` (`name`) ) CREATE TABLE `Category` ( `id` smallint(4) unsigned NOT NULL, `name` varchar(100) NOT NULL, UNIQUE KEY `id` (`id`), KEY `name` (`name`), ) </code></pre> <p>Here: </p> <pre><code>+----+-------------+-------+--------+----------------------------------------+----------+---------+----------------------------+------+-------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +----+-------------+-------+--------+----------------------------------------+----------+---------+----------------------------+------+-------------+ | 1 | SIMPLE | b | index | NULL | name | 258 | NULL | 15 | | | 1 | SIMPLE | a | eq_ref | cat_id_3,cat_id,book_id,library_id | cat_id_3 | 7 | const,b.id,const | 1 | Using index | | 1 | SIMPLE | c | const | PRIMARY | PRIMARY | 2 | const | 1 | Using where | +----+-------------+-------+--------+----------------------------------------+----------+---------+----------------------------+------+-------------+ </code></pre>

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