OCI-06506
PL/SQL: native call stack exhausted at a depth of string calls
Cause
PL/SQL native execution has exhausted the stack memory of the process. It is typically caused by deeply recursive programs.
Action
Refactor code to use iteration rather than recursion. If this does not work or is unpreferred, set the PLSQL_OPTIMIZE_LEVEL parameter to 1 and recompile. Contact Oracle Support if neither work.