How do you version your database schema? [closed]

Answer 1

See

Is there a version control system for database structure changes?

How do I version my MS SQL database in SVN?

and Jeff's article

Get Your Database Under Version Control

I feel your pain, and I wish there were a better answer. This might be closer to what you were looking for.

Mechanisms for tracking DB schema changes

Generally, I feel there is no adequate, accepted solution to this, and I roll my own in this area.

Answer 2

We're exporting the data to a portable format (using our toolchain), then importing it to a new schema. no need for delta SQL. Highly recommended.

Answer 3

I use http://code.google.com/p/oracle-ddl2svn/

Answer 4

I use Firebird database for most development and I use FlameRobin administration tool for it. It has a nice option to log all changes. It can log everything to a one big file, or one file per database change. I use this second option, and then I store each script in version control software - earlier I used Subversion, now I use Git.

I assume you can find some MySQL tool that has the same logging feature like FlameRobin does for Firebird.

In one of database tables, I store the version number of the database structure, so I can upgrade any database easily. I also wrote a simple PHP script that executes those SQL scripts one by one on any target database (database path and username/password are supplied on the command line).

There's also an option to log all DML (insert, update delete) statements, and I activate this while modifying some 'default' data that each database contains.

I wrote a nice white paper on how I do all this in detail. You can download the paper in .pdf format along with demo PHP scripts from here.

Answer 5

I also developed a set of PHP scripts where developers can submit their deltasql scripts to a central repository.

In one of the database tables (called TBSYNCHRONIZE), I store the version number of the latest executed script, so I can upgrade any database easily by using the web interface or a client developed on purpose for Eclipse.

The web interface allows to manage several projects. It supports also database "branches".

You can test the application at http://www.gpu-grid.net/deltasql (if you login as admin with password testdbsync). The application is open source and can be downloaded here: http://sourceforge.net/projects/deltasql

deltasql is used productively in Switzerland and India, and is popular in Japan.

Answer 6

I make sure that schema changes are always additive. So I don't drop columns and tables, because that would zap the data and cannot be rolled back later. This way the code that uses the database can be rolled back without losing data or functionality.

I have a migration script that contains statements that creates tables and columns if they don't exist yet and fills them with data.

The migration script runs whenever the production code is updated and after new installs.

When I would like to drop something, I do it by removing them from the database install script and the migration script so these obsolete schema elements will be gradually phased out in new installs. With the disadvantage that new installs cannot downgrade to an older version before the install.

And of course I execute DDLs via these scripts and never directly on the database to keep things in sync.