Use schema comparison for these
purposes:
- Different versions of the same schema to manage changes to the
schema.
- Two schemas from different databases so you can merge the schemas
(for example, merge a checkout system with a production system).
Use these steps to compare schema:
- Create a baseline sample of one schema using XML export. See
Creating a Baseline.
- Analyze the differences between the baseline sample and the other
schema (or a later version of the same schema) using the compare command. You
specify the administrative types (attributes, relationships, and so on) and a
name pattern (for example, all attributes beginning with "Supplier") to
compare. Each compare command outputs a single log file that contains a report.
The report lists the administrative objects in the baseline export file that
have been added, deleted, and modified. See
Comparing a Schema with the Baseline.
If your goal is to merge the two schemas by making the necessary
changes to one of the schemas (sometimes called "applying a delta"), you can
make the changes manually or write an
MQL
script file that applies the changes to the target schema.