Answer by dmann ·
Depends on the tool you are using.
If you are using SQLPLUS and you commit code to the database and it complains about errors, just use this command:
If you are looking for invalid objects in the database you can always run a query against DBA_OBJECTS:
SELECT OBJECT_NAME, OBJECT_TYPE FROM DBA_OBJECTS WHERE STATUS='INVALID';
If you are using a graphical tool (like Toad, SQL Developer) you can usually browse for invalid pl/sql objects (usually indicated with a "Red X" next to it in the pick lists). Open the object, run the compile command, and the tool will usually show you exactly where there error is and a short description about it.