[Solved] Oracle ORDER BY with rownum or HAVING >= ALL

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: 4): 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
        * 
    FROM
        (SELECT
            points.groupid,
            AVG(points.score) average 
        FROM
            points 
        WHERE
            points.yr = 2010 
            AND points.score IS NOT NULL 
        GROUP BY
            points.groupid 
        ORDER BY
            average DESC) 
    WHERE
        rownum = 1

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* original question posted on StackOverflow here.