[Solved] How to optimize or speed up my subquery in mysql or in php

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. 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 `table1` ADD INDEX `table1_idx_datecreated` (`dateCreated`);
ALTER TABLE `table2` ADD INDEX `table2_idx_t2_id` (`t2_id`);
ALTER TABLE `table3` ADD INDEX `table3_idx_logid_logs` (`logid`,`logs`);
ALTER TABLE `table3` ADD INDEX `table3_idx_logs` (`logs`);
The optimized query:
SELECT
        table1.t1_id,
        table1.name,
        table2.address,
        (SELECT
            message 
        FROM
            table3 
        WHERE
            table3.logid = table1.t1_id 
            AND message NOT LIKE "[ SYSTEM%" 
        ORDER BY
            table3.logs DESC LIMIT 1) AS message 
    FROM
        table1 
    INNER JOIN
        table2 
            ON table1.t1_id = table2.t2_id 
    WHERE
        table1.dateCreated BETWEEN CAST('2015-01-01' AS Date) AND CAST('2015-05-30' AS Date) 
    ORDER BY
        table1.dateCreated DESC

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* original question posted on StackOverflow here.