[Solved] MYSQL if a status is liked by a user include it in query results

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.
  2. Use Numeric Column Types For Numeric Values (query line: 26): Referencing a numeric value (e.g. 4) as a string in a WHERE clause might result in poor performance. Possible impacts of storing numbers as varchars: more space will be used, you won't be able to perform arithmetic operations, the data won't be self-validated, aggregation functions like SUM won't work, the output may sort incorrectly and more. If the column is numeric, remove the quotes from the constant value, to make sure a numeric comparison is done.
  3. Use Numeric Column Types For Numeric Values (query line: 27): Referencing a numeric value (e.g. 5) as a string in a WHERE clause might result in poor performance. Possible impacts of storing numbers as varchars: more space will be used, you won't be able to perform arithmetic operations, the data won't be self-validated, aggregation functions like SUM won't work, the output may sort incorrectly and more. If the column is numeric, remove the quotes from the constant value, to make sure a numeric comparison is done.
Optimal indexes for this query:
ALTER TABLE `updates` ADD INDEX `updates_idx_uid_fk_type` (`uid_fk`,`type`);
ALTER TABLE `updates` ADD INDEX `updates_idx_created` (`created`);
ALTER TABLE `users` ADD INDEX `users_idx_college_uid` (`college`,`uid`);
The optimized query:
SELECT
        b.type,
        b.owner,
        b.update_img,
        b.ALBUM_ID,
        b.last_comment,
        a.uid,
        a.first_name,
        a.last_name,
        a.gender,
        a.thumb_img,
        b.msg_id,
        b.message,
        b.created,
        b.POST_PRIVACY 
    FROM
        users AS a,
        updates AS b,
        LIKED AS c 
    WHERE
        b.uid_fk = a.uid 
        AND b.type <> 'FRIEND_RELATIONSHIP' 
        AND b.created < $time 
        AND b.type <> 'FAMILIAR_RELATIONSHIP' 
        AND a.college = '$college' 
        AND b.POST_PRIVACY <> '4' 
        AND b.POST_PRIVACY <> '5' 
        AND b.created >= $tstamp 
    ORDER BY
        b.created DESC LIMIT 100

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* original question posted on StackOverflow here.