Christophe,
I agree with Dr. DeSoi that it may not always be possible to automate
schema transformations. However, if you need to compare the metadata
between two databases, the free, open-source SchemaCrawler for SQL
Server tool will do this for you. You can take human-readable
snapshots of the schema and data, for later comparison. Comparisons
are done using a standard diff tool such as WinMerge. SchemaCrawler
outputs details of your schema (tables, views, procedures, and more)
in a diff-able plain-text format (text, CSV, or XHTML). SchemaCrawler
can also output data (including CLOBs and BLOBs) in the same plain-
text formats.
SchemaCrawler is available at SourceForge:
http://schemacrawler.sourceforge.net/
Sualeh Fatehi