[Solved] Rewrite SQL query with JOINS in JPA

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 (query line: 9): We advise against using subqueries as they are not optimized well by the optimizer. Therefore, it's recommended to join a newly created temporary table that holds the data, which also includes the relevant search index.
The optimized query:
SELECT
        @ref := id AS id,
        unique_id,
        reference_id 
    FROM
        mytable 
    JOIN
        (
            SELECT
                @ref := id 
            FROM
                mytable 
            WHERE
                mytable.unique_id = 55544
        ) tmp 
    WHERE
        reference_id = @ref

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* original question posted on StackOverflow here.