Database objects becoming invalid

The Oracle database will invalidate objects if a dependent object is changed. If I rebuild a table, the indexes on that table will become invalid because they use the table's rowids and rebuilding the table changes a row's rowid. It is the same with objects like packages, procedures and functions. In a development environment with lots of users working on the same objects this can become aggravating. Just remember that someone caused the database to invalidate the object. You can control this by controlling who changes objects in the database, or splitting the development into multiple schemas so that one section does not cause another's objects to become invalid.