The materialized views(MV) are refreshed nightly, but the Last DDL date noted in the schema browser doesn't reflect the change. If the MV is altered manually, the Last DDL is updated.
This was not an issue when working with 9i databases and only an issue after upgrading to 11g databases.
Issue with difference between 9i database and 11g database.
Last DDL will not reflect a change based off of a refresh.
Check the Last Refresh date for this info. Right click header on the left hand side of the Schema Browser, above the list of MVs. Choose to show "Last Refresh". A column with the time and date of the Last Refresh will display along with the name of the MV in the list on the left hand side.
