Alzabo::MySQL(3pm)					User Contributed Perl Documentation					Alzabo::MySQL(3pm)

NAME

       Alzabo::MySQL - Alzabo and MySQL

DESCRIPTION

       This documentation is about what special support Alzabo has for MySQL, as well as what is lacking.

       MySQL support is based on the 3.23.* release series, with some support for features that are starting to appear in the 4.0.* releases.
       Earlier versions of MySQL will probably work with Alzabo, though Alzabo cannot magically make these releases support new features like
       fulltext indexes.

       Indexes

       o   Alzabo supports the ability to specify prefixes when adding an index.  Prefixes are required when attempting to index any sort of text
	   or blob column.

       o   Alzabo supports the creation of fulltext indexes and their use in SELECT and WHERE clauses.	This includes the ability to get back the
	   score given for a match as part of a select, using the "function" or "select" methods of either table or schema objects.

       Reverse Engineering

       o   When reverse engineering a schema, Alzabo knows that MySQL has "default defaults" for certain column types.	For example, if a DATE
	   column is specified as NOT NULL but is not assigned a default, MySQL gives this column a default of '0000-00-00'.

	   Because Alzabo knows about this, it will ignore these defaults when reverse engineering an RDBMS.

       o   Similarly, Alzabo knows that MySQL assigns default "lengths" to many column types.  For example, if given INTEGER as a column type,
	   MySQL will convert this to INTEGER(11) or INTEGER(10), depending on the version of MySQL being used.

	   Again, Alzabo ignores these lengths when reverse engineering a schema.

       o   All of this may lead to apparent inconsistencies when using the with the "Alzabo::Create::Schema->sync_backend" or "Alzabo::Cre-
	   ate::Schema->sync_backend_sql" methods.  If you are using this feature from the web based schema creator, you will see that even imme-
	   diately after running the "sync_backend()" method, Alzabo may still think there are differences between the two schemas.  This is not a
	   problem, as running the SQL Alzabo generates will not actually change your database.

       Transactions

	   Alzabo will try to use transactions whenever appropriate.  Unfortunately, there is no way to determine whether or not a given table
	   supports transactions so Alzabo simply calls DBI's "begin_work()" method, whether or not this will actually do anything.

       Constraints and Foreign Keys

       o   Column constraints are treated as column attributes.

       o   Foreign key constraints are not generated when generating SQL for a MySQL schema.  This will probably change in the future.

       Table Types

	   These can be specified as a table attribute.

perl v5.8.8							    2007-12-23							Alzabo::MySQL(3pm)