[Solved] Performance issues with outer joins to view in Oracle 12c

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 Selecting Unnecessary Columns (query line: 2): Avoid selecting all columns with the '*' wildcard, unless you intend to use them all. Selecting redundant columns may result in unnecessary performance degradation.
  2. 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:
CREATE INDEX policyissuance_oas_idx_policyn_datecha_newtran_followu ON policyissuance_oasis (policyNumber,DateChars,newTranKeyJoin,followup_time);
CREATE INDEX policytransaction__idx_poltrankeyjoin ON policytransaction_oasis (polTranKeyJoin);
The optimized query:
SELECT
        pi.*,
        pt.* 
    FROM
        policyissuance_oasis pi,
        policytransaction_oasis pt 
    WHERE
        pi.newTranKeyJoin = pt.polTranKeyJoin(+) 
        AND pi.policyNumber = '1-H000133' 
        AND pi.DateChars = '08/10/2017 09:24:51' 
    ORDER BY
        pi.followup_time

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* original question posted on StackOverflow here.