Search notes:

PLW-06003: unknown inquiry directive '$$…'

The warning PLW-06003: unknown inquiry directive '$$…' occurs if the source code references a preprocessor directive whose value was not explicitly set in plsql_ccflag.
create or replace procedure tq84_proc
   authid definer
as begin

  $if $$xyz $then
      dbms_output.put_line('xyz is defined');
  $else
      dbms_output.put_line('xyz is not defined');
  $end

end tq84_proc;
/
In order to prevent this warning, $$xyz must be set to a value:
alter session set plsql_ccflags = 'xyz:true';

See also

Oracle PL/SQL: Errors and warnings

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