[Solved] Join two tables, matching a column with multiple values

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 Selecting Unnecessary Columns (query line: 2): Avoid selecting all columns with the '*' wildcard, unless you intend to use them all. Selecting redundant columns may result in unnecessary performance degradation.
  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 `parametersitems` ADD INDEX `parametersitems_idx_parameterid_itemid` (`ParameterID`,`ItemID`);
The optimized query:
SELECT
        products.* 
    FROM
        products 
    INNER JOIN
        parametersitems AS paritems1 
            ON paritems1.ItemID = products.ID 
            AND paritems1.ParameterID = 7 
    INNER JOIN
        parametersitems AS paritems2 
            ON paritems2.ItemID = products.ID 
            AND paritems2.ParameterID = 11

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* original question posted on StackOverflow here.