Please be aware no hidden parameters (parameters starting with “_”) should not be set unless recommended by Oracle explicitly or in case of a perfect match to the case.
This is explained on MOS Best Practices and Guidelines for Setting underScore/Hidden Parameter to Workaround and/or Resolve Customers Problems (Doc ID 2524119.1)
So, in case of any diagnostics you have to lead to setting it, SUGGESTED:
- Get the explicit approval/agreement from Oracle.
- Include evidence on the root cause for this setting. A comment should work, something like:
alter system set "_replace_virtual_columns"=false Comment= 'Workaround Doc ID 1512347.1' SID= '*' scope= both;
Cheers!