[Solved] inner join slow performance

How to optimize this SQL query?

In case you have your own slow SQL query, you can optimize it automatically here.

For the query above, the following recommendations will be helpful as part of the SQL tuning process.
You'll find 3 sections below:

  1. Description of the steps you can take to speed up the query.
  2. The optimal indexes for this query, which you can copy and create in your database.
  3. An automatically re-written query you can copy and execute in your database.
The optimization process and recommendations:
  1. Avoid Subqueries In From Clause (modified query below): The database cannot properly optimize subqueries in the FROM clause. Therefore, we recommend to extract the subqueries to temporary tables, index them and join to them in the outer query.
  2. Create Optimal Indexes (modified query below): The recommended indexes are an integral part of this optimization effort and should be created before testing the execution duration of the optimized query.
Optimal indexes for this query:
ALTER TABLE `categories_groups_cat1` ADD INDEX `categories_cat1_idx_id` (`id`);
ALTER TABLE `es_temp1` ADD INDEX `es_temp1_idx_categories_id` (`categories_groups_cat1_id`);
ALTER TABLE `es_temp2` ADD INDEX `es_temp2_idx_id` (`id`);
ALTER TABLE `es_temp3` ADD INDEX `es_temp3_idx_category_gr` (`category_gr`);
The optimized query:
SELECT
        cat1.id AS cat1id,
        cat1.title_gr AS title,
        cat1.order 
    FROM
        categories_groups_cat1 AS cat1 
    INNER JOIN
        es_temp1 AS vs 
            ON vs.categories_groups_cat1_id = cat1.id 
    INNER JOIN
        es_temp2 AS cats 
            ON cats.id = vs.categories_id 
    INNER JOIN
        es_temp3 AS offers 
            ON offers.category_gr = cats.title_gr 
    GROUP BY
        cat1.id 
    ORDER BY
        cat1.order ASC

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