All SchemaCrawler output formats are designed to be easy to diff, or find differences with other schemas that may have been output in the same format.
Diff-ing Schemas Using the SchemaCrawler Command-line
In order to diff schemas, you will need to run SchemaCrawler twice, once against each database. Each time, you will need to generate an output file in the same format. SchemaCrawler’s text format allows for the best diff.
Once you have two files, you can use a standard diff tool, such as Beyond Compare to find the differences between the two schemas.
You can even compare databases with similar tables, even if they are for two different kinds of database systems, such as Oracle and Microsoft SQL Server.
Diff-ing Schemas Programatically
You can diff schemas from two different database programatically as well, using SQiShER’s excellent java-object-diff library. You will first need to connect to each database separately, and use SchemaCrawler to obtain database metadata in SchemaCrawler’s object model. If you need an example on how to do this, please study the sample code in the SchemaCrawler diff project.