Hello.
I want to be able to migrate schema changes from a DataMap to a
database. Mainly for two reasons.
1) Make it easier for DBAs and developers to keep track of DB
related changes in a project.
2) Make it simpler for developers to keep the db schema in sync
with the model.
My current implementation has support for adding tables, add/drop
columns, setting null/not null and changing text length. The unit
tests works on PostgreSQL, MS SQL Server and Derby.
Implementation details:
* Each DbAdapter can create a DbMergerFactory that are able to
create DbMergerToken for various tasks like AddColumn and SetAllowNull.
* A DbMerger class that uses DbLoader to create a DataMap from the
db and then create a List of needed DbMergerTokens that can be
applied to the database to get in sync.
Here are some screenshots from the modeler.
http://www.pvv.ntnu.no/~halset/tmp/caymigr/
TODO:
* Support more databases. Will need help on this one as I do not
have access to that many.
* Default value for not null columns.
* Support more tasks like adding/dropping forreign keys, changing
primary keys and so on.
We have discussed this before, but I am not able to find a suitable
jira task for it.
Is this something you want for cayenne as well? Is it ok for you if I
start checking in after M2?
Regards,
- Tore.
