This tip was found in Oracle forums. With due respect to the author I am replicating the idea of the message below:
Oracle introduced conditional compilation of packages/procedures from 10g.
Conditional compilation allows PL/SQL code to be tailored to specific environments by selectively altering the source code based on compiler directives. It is considered a new feature of Oracle 10g Release 2, but is available in Oracle 10g Release 1 (10.1.0.4.0).
Compiler flags are identified by the "$$" prefix, while conditional control is provided by the $IF-$THEN-$ELSE syntax.
$IF boolean_static_expression $THEN text
[ $ELSIF boolean_static_expression $THEN text ]
[ $ELSE text ]
$END
Find below a simple example of procedure that uses conditional compilation. The objective of this package is to invalidate the package by not modifying the source/underlying objects.
SQL> create or replace package p is $IF ($$x) $then INVALID $else $end end;
/
Package created.
SQL> select status from user_objects where object_name='P';
STATUS
-------
VALID
SQL> alter package p compile PLSQL_CCFLAGS='x:true';
Warning: Package altered with compilation errors.
SQL> select status from user_objects where object_name='P';
STATUS
-------
INVALID
Thus without modifying the actual contents of the package we have been successful in invalidating the package.
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