MySQL-PHP-AutoMigrations: A PHP repository from Billiam

MySQL-PHP-AutoMigrations is a fork of mysql-php-migrations
( http://code.google.com/p/mysql-php-migrations/ )

The original project has been altered primarily to help keep
database schema in sync between branches during development.

When run, the actual content of a migration is now stored in the
database. This means that when migrating downwards, the contents
of the migrations directory are not important.

==NEW ARGUMENTS==
+------------------------+
| Auto, most importantly |
+------------------------+
Auto is designed to be used when the migrations directory changes,
such as after a branch checkout. There may be new migrations, and
 some completed migrations may be absent.

Auto will compare migrations that have been run to the available
patches in the migrations directory, migrate down to the oldest
shared migration (using the database of stored migrations, not the
files in the directory), and then migrate back up to the newest
migration in the directory.

--- Example: ---
Suppose the following migrations have already been run in your
current branch (branch-b) :
2010_01_01_02_49_23_add_table_indices.php
2010_02_13_01_11_57_delete_payments_table.php
2010_04_13_13_21_36_insert_new_payment_types.php

You then switch to another branch (branch-a) that has an earlier
base. This branch has the following patches:
2010_01_01_02_49_23_add_table_indices.php
2010_05_12_14_23_08_video_table_simplification.php

This branch contains some code that's still looking for the payments
table, causing query errors. Your database schema is no longer in
sync.

Without automigrations, you might need to:
1. check out branch-a
2. note that the oldest shared patch between branch-a and branch-b 
   is: add_table_indices
3. check out branch-b again
4. migrate down to this shared patch (add_table_indices)
5. check out branch-a
6. migrate up to newest patch (video_table_simplification)

With automigrations
1. check out branch-a
2. run auto function

Switching back to branch-b is easy, too
1. check out branch-b
2. run auto function

This is very useful for development, but a production server will
probably not affect a production server, which will just run
migrate.php latest.

+---------+
| Propose |
+---------+
Simply prints the actions that auto would take if it were run.



==OTHER SIGNIFICANT CHANGES==
Text strings after timestamps in migration filenames are allowed.
2010_05_12_14_23_08_video_table_simplification.php
instead of 
2010_05_12_14_23_08.php

Again, this is to ease branching in multi-developer environments.


Improved schema creation from this suggestion: 
http://code.google.com/p/mysql-php-migrations/issues/detail?id=4
Billiam/MySQL-PHP-AutoMigrations
