Common Best Practices for Setting Up Oracle Search

If you're setting up Oracle Search across your Fusion environment for the very first time, then:

Ensure that you set the ORA_FND_SEARCH_EXT_ENABLED profile option to Y.
Run the ESS job to create index definition and perform initial ingest to OSCS scheduled process to perform the initial functional index ingestion for your module.

If Oracle Search is already set up for a given product in your Fusion environment and you're setting it up for your product or module for the very first time, then run the ESS job to create index definition and perform initial ingest to OSCS scheduled process to perform the initial functional index ingestion for your module.

Run the scheduled process for bulk ingestion at least once a day or as often as your business requires to keep the index up to date.

Run health checks of functional index ingestion with diagnostic reports periodically to identify any ingestion issues.

For HCM, there are reports for person, journeys, work structures, and so on. In addition, run Compute Users ACL with population = All Users after P2T (on the target environment).
For SCM, you can generate reports of item indexes for missing or duplicate items as described in Analyze Index.

For Item and Sales Order index in SCM, add all attributes that you need in one go so you don’t have to rebuild the index multiple times. Each rebuild is a full rebuild and could take extremely long to complete, even if you’ve added only one attribute.

Don't schedule the ingestion of functional indexes. It’s unnecessary and might consume significant system resources.

Except for Item and Sales Order index in SCM, don’t run initial ingestion of functional indexes (such as fa-hcm-person or fa-prc-suppliers) as part of the release upgrade. There's an automated ingestion process implemented, which will reingest indexes that require full reingestion upon release upgrade.