Depending on which features are installed and configured, an Oracle 10g database can contain more than 1,300 data dictionary views.
Data dictionary views have names that begin with DBA_,ALL_, and USER_.
-The DBA_TABLES view shows information on all the tables in the database.
-ALL_TABLES view, shows only the tables that a particular database user owns or has access to.
For example, if you were logged into the database as a user named PROD7, the ALL_TABLES view would show all the tables owned by the user PROD7 and the tables to which PROD7 has been granted access by other users.
-USER_TABLES view shows only those objects owned by a user.
For example, If the user PROD7 were to examine the USER_TABLES view, only those tables he owns would be displayed.
