Hello, on 04/11/2007 12:13 PM Richard Davey said the following: > Hi all, > > I know a lot of you use various means for PHP source control (CVS, SVN, > etc), which is all well and fine, but how do you manage source control > on your databases? > > Say you've got an upgrade to a site, all of the new PHP files are > controlled by SVN, so you can rollback at any time, but say the upgrade > includes several key modifications to a MySQL table and perhaps the > changing of some core data. > > How (if at all?!) do you handle the versioning of the database and data > itself, so you can keep both PHP and SQL structure in sync? In 1998 I started a project to address very similar needs to yours. I wanted to develop database independent applications that would let me not only access different databases with the same API, but also would let me install and maintain database schemas, also in a database independent fashion. I created a XML format to declare the database tables, fields, indexes, sequences, etc.. Then the package reads the schema definitions and installs the schema in whatever database I use. If I need to change my database schema, I just change the database definition and tell my package to compare the present and the installed schema versions in order to perform the necesssary changes to upgrade the schema, all without disturbing data that was inserted since the schema was installed for the first time or upgraded for the last time. Since the schema definition is now just a XML file, I can keep track of successive revisions in CVS. If I want to downgrade the schema, I just checkout the respective versions and tell my package to update the installed schema just like when it is upgraded. This package that I developed is named Metabase. It became very popular and many of its ideas were copied. There is also a PEAR style flavour for PEAR fans, named MDB. PEAR MDB2 is MDB follow up version. Until today there are several other PHP database abstraction layers that use the same XML schema definition format. Metabase is available here: http://www.phpclasses.org/metabase Here you may also find some documentation: http://www.meta-language.net/documentation.html#metabase -- Regards, Manuel Lemos Metastorage - Data object relational mapping layer generator http://www.metastorage.net/ PHP Classes - Free ready to use OOP components written in PHP http://www.phpclasses.org/ -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
