[Solved] How can I use the result of this query as source of another query that extract n random records?

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: 7): 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
        name 
    FROM
        random AS r1 
    JOIN
        (
            SELECT
                (RAND() * (SELECT
                    MAX(id) 
                FROM
                    random)) AS id) AS r2 
            WHERE
                r1.id >= r2.id 
            ORDER BY
                r1.id ASC LIMIT 3

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* original question posted on StackOverflow here.