[Solved] Materialized View returns more results than the query itself Oracle

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: 30): 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
        cos.process_number,
        cos.status,
        cos.LASTCHANGEUSER,
        date_time,
        rank() OVER (PARTITION 
    BY
        cos.process_number 
    ORDER BY
        cos.date_time DESC) rank 
    FROM
        (SELECT
            process_number,
            status,
            grp,
            LASTCHANGEUSER,
            min(jn_datetime) OVER (PARTITION 
        BY
            process_number,
            grp 
        ORDER BY
            jn_datetime) AS date_time,
            rank() OVER (PARTITION 
        BY
            process_number,
            grp 
        ORDER BY
            jn_datetime) AS aux_rank 
        FROM
            (SELECT
                process_jn.process_number,
                process_jn.jn_datetime,
                process_jn.status,
                process_jn.LASTCHANGEUSER,
                row_number() OVER (PARTITION 
            BY
                process_number 
            ORDER BY
                process_jn.jn_datetime) - row_number() OVER (PARTITION 
            BY
                process_number,
                status 
            ORDER BY
                process_jn.jn_datetime) grp 
            FROM
                process_jn)) cos 
        WHERE
            aux_rank = 1

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* original question posted on StackOverflow here.