Error: Check if all adaptive features parameters are unset

| Added: June 30, 2025 | Total views: 93

Problem Installing Oracle Enterprise Manager 13c on Oracle Database 21c

Error: Check if all adaptive features parameters are unset

When installing Oracle Enterprise Manager (OEM) 13.5 on Oracle Database 21c, you may encounter the error:

Check if all adaptive features parameters are unset

The log file will contain entries similar to:

Recommendation : All adaptive features parameters should be unset for improved SQL performance
CorrectionType : Manual
Log Location : /tmp/OraInstall2025-06-30_07-35-32AM/emdbprereqs/LATEST/emprereqkit.out

Even after following all recommendations and executing the commands:

ALTER SYSTEM RESET "_optimizer_nlj_hj_adaptive_join" SCOPE=BOTH SID='*';

ALTER SYSTEM RESET "_optimizer_strans_adaptive_pruning" SCOPE=BOTH SID='*';

ALTER SYSTEM RESET "_px_adaptive_dist_method" SCOPE=BOTH SID='*';

ALTER SYSTEM RESET "_sql_plan_directive_mgmt_control" SCOPE=BOTH SID='*';

ALTER SYSTEM RESET "_optimizer_dsdir_usage_control" SCOPE=BOTH SID='*';

ALTER SYSTEM RESET "_optimizer_use_feedback" SCOPE=BOTH SID='*';

ALTER SYSTEM RESET "_optimizer_gather_feedback" SCOPE=BOTH SID='*';

ALTER SYSTEM RESET "_optimizer_performance_feedback" SCOPE=BOTH SID='*';

...the installer still fails. The problem is not with the parameters themselves, but with the choice of database version.

❌ Why Oracle Database 21c is not a good choice for OEM 13c

Oracle 21c is an innovation release, which means:

No long-term support (LTS),
Short lifecycle (only 18 months of support),
Experimental features,
Often lacks backward compatibility for infrastructure tools.

Oracle does not certify OEM 13c with Oracle 21c.

Officially supported database versions for OEM 13c:

Oracle 12.2.0.1
Oracle 18c
Oracle 19c (recommended: LTS, full support)
(sometimes Oracle 11g for legacy environments)

⚠️ What happens when using 21c?

OEM 13c has not been tested with 21c — installation might work, but Oracle does not guarantee functionality or support.
Parameters required by OEM may have been deprecated or changed.
Even if adaptive feature parameters are properly reset, the installer may still detect them as non-compliant.

✅ Solution

Switch the database used by OEM 13c to Oracle 19c.

Oracle Database 19c is a Long-Term Support (LTS) release.
It is officially supported and recommended by Oracle for OEM 13c.
Installation proceeds without errors, and the adaptive parameter checks pass successfully.

Summary

If you encounter the error "Check if all adaptive features parameters are unset" while installing OEM 13c on Oracle 21c .

Solution: use a supported database version (e.g., 19c) that is listed in Oracle’s documentation.

References:

Oracle Enterprise Manager 13.5 Installation Guide
https://stackoverflow.com/questions/70541881/oem-13-error-check-if-all-adaptive-features-parameters-are-unset

Aleksander Legkoszkur

Database Administrator

A technology fan who likes to stayes at night until he finds a solution. A small handyman who tries to fix everything he can get his hands on. Worked with technologies like:

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