[Solved] Keep SQL query general and make it fast

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 Correlated Subqueries (query line: 18): A correlated subquery is a subquery that contains a reference (column: t_col_2) to a table that also appears in the outer query. Usually correlated queries can be rewritten with a join clause, which is the best practice. The database optimizer handles joins much better than correlated subqueries. Therefore, rephrasing the query with a join will allow the optimizer to use the most efficient execution plan for the 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 `actual_table` ADD INDEX `actual_table_idx_id_pid` (`ID`,`PID`);
The optimized query:
WITH temp_table (t_col_1, t_col_2, t_col_3) AS (SELECT
        actual_table.col_1 AS t_col_1,
        actual_table.col_2 AS t_col_2,
        actual_table.col_3 AS t_col_3 
    FROM
        actual_table 
    WHERE
        actual_table.ID = 100 
        AND actual_table.PID = 1245) SELECT
        t1.t_col_1,
        t1.t_col_2,
        t1.t_col_3 
    FROM
        temp_table AS t1 
    WHERE
        t1.t_col_2 BETWEEN 1 AND 12541 
        AND t1.t_col_1 = (
            SELECT
                max(t2.t_col_1) 
            FROM
                temp_table AS t2 
            WHERE
                t2.t_col_1 < 15147 
                AND t2.t_col_2 = t1.t_col_2
        ) 
    ORDER BY
        t1.t_col_2

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* original question posted on StackOverflow here.