Operations such as upgrades, patches and DDL changes can cause invalid schema objects.
At this situation, you should recompile the invalid objects.

Identifying Invalid Objects

To see which objects are invalid, you can use the dba_objects view.
Simple, use the following sql query.

SELECT owner, object_type, object_name, status
FROM dba_objects
WHERE status = 'INVALID' ORDER BY owner, object_type, object_name;

Recompiling Invalid Objects
There are a few method to re-compile invalid objecst.
If you are using SQL Navigator as many DBA, simple, right click the invalid procedure and give the compile command.
Otherwise, you should compile invalid objects manually. Use the one of the following examples.

ALTER PACKAGE my_package COMPILE;
ALTER PACKAGE my_package COMPILE BODY;
ALTER PROCEDURE my_procedure COMPILE;
ALTER FUNCTION my_function COMPILE;
ALTER TRIGGER my_trigger COMPILE;
ALTER VIEW my_view COMPILE;

How to be notified when an object became invalid ?

Invalid objects can cause really serious problems in your production system. You must watch your database and check invalid objects after the every changes.

If you want, netAlarm can check invalid objects periodically for you. If it founds an invalid object in your database, it can notify you without losing any time.

If you want to see additional monitoring features implemented in NetAlarm, we would please to hear.
Please Click here