DBDiff for Oracle is a database utility that performs a comparison between two Oracle databases and can also automatically create scripts to upgrade from one database to the other.
Any Oracle database can be compared, the databases do not need to be on the same version of Oracle (7.3.3, 7.3.4, 8, 9, etc), they don’t even need to be on the same machine, as long as they are both accessible from the machine running DBDiff.
 

DBDiff uses a carefully planned and designed algorithm for performing the quickest, most accurate comparison between the databases; this algorithm allows for multiple levels of comparison to be performed on the databases.

Privilege Comparison - This level will perform a comparison between all privileges granted to the user, System privileges, Role privileges and/or Object privileges are compared.

Sequence Comparison - This level will perform a comparison between all sequences found on the databases, it can also compare the "last value" of the sequences.

Table Structure Comparison - This level will perform a comparison between all table structures accessible to the user.

Index Comparison - This level will perform a comparison between all the indexes found on all the tables that are common to the databases.

Constraint Comparison - This level will perform a comparison between all constraints found on the databases, both System generated constraints and/or User generated constraints are compared.

Table Data Comparison - This level will perform a comparison of all the data found in common tables (including their columns) between the databases. It uses a heuristic algorithm to place the rows that have differences in a manner that “makes sense” for the user to review.

View Data Comparison - This level will perform a comparison of all the data found in common views.

Trigger Comparison - This level will perform a comparison between all triggers.

View Structure Comparison - This level will perform a comparison between all views' source.

Function Comparison - This level will perform a comparison between all the functions.

Package Comparison - This level will perform a comparison between all the packages.

Package Body Comparison - This level will perform a comparison between all the packages body.

Stored Procedure Comparison - This level will perform a comparison between all the stored procedures.

Type Comparison - This level will perform a comparison between all the types.

Type Body Comparison - This level will perform a comparison between all the types body.

In order to make it easy to understand the output of the comparison, DBDiff for Oracle creates a report that includes all the differences in a user friendly manner. Also reported is other useful information about the databases and the comparison.