You don’t have to wait for Oracle 23ai to use these new cool features

Starting with Oracle 19.28, the use of IF [NOT] EXISTS and the function DBMS_SQLDIAG.REPORT_SQL is now available. Learn all about them.
Troubleshoot: a non-regular solution for “ORA-01502 index is in unusable state”

How an error caused by running analyze on a table with unusable indexes is solved with regular expressions and dbms_stats.
How to hide PL/SQL source code? Use Wrap
How to hide stored PL/SQL source code: packages, procedures, and functions in Oracle, using the wrap utility