When you upgrade templated based Oracle installation the system-sphinx will fail with this error:
indexing index 'account_delta'... ERROR: index 'account_delta': sql_query_range: : range-query failed: [Oracle][ODBC][Ora]ORA-30076: invalid extract field for extract source (DSN=odbc://dballo02:***@oracle-12cr2-cdb.mwqe.upshift.rdu2.redhat.com:1521/pdb1).
I have used this documentation for the whole process https://gitlab.cee.redhat.com/red-hat-3scale-documentation/3scale-documentation/merge_requests/258
EDIT: It fails with both templates and operator upgrade