The dbx module is a database abstraction layer (db 'X', where 'X' is a supported database). The dbx functions allow you to access all supported databases using a single calling convention. The dbx-functions themselves do not interface directly to the databases, but interface to the modules that are used to support these databases.
Note: This extension has been moved to the PECL repository and is no longer bundled with PHP as of PHP 5.1.0.
To be able to use a database with the dbx-module, the module must be either linked or loaded into PHP, and the database module must be supported by the dbx-module. Currently, the following databases are supported, but others will follow:
FrontBase (available from PHP 4.1.0).
Sybase-CT (available from PHP 4.2.0).
Oracle (oci8) (available from PHP 4.3.0).
SQLite (PHP 5).
Documentation for adding additional database support to dbx can be found at http://www.guidance.nl/php/dbx/doc/.
In order to have these functions available, you must compile PHP with dbx support by using the --enable-dbx option and all options for the databases that will be used, e.g. for MySQL you must also specify --with-mysql=[DIR]. To get other supported databases to work with the dbx-module refer to their specific documentation.
The behaviour of these functions is affected by settings in php.ini.
Table 1. DBX Configuration Options
Name | Default | Changeable | Changelog |
---|---|---|---|
dbx.colnames_case | "unchanged" | PHP_INI_SYSTEM | Available since PHP 4.3.0. |
Here's a short explanation of the configuration directives.
Columns names can be returned "unchanged" or converted to "uppercase" or "lowercase". This directive can be overridden with a flag to dbx_query().
There are two resource types used in the dbx module. The first one is the link-object for a database connection, the second a result-object which holds the result of a query.
The constants below are defined by this extension, and will only be available when the extension has either been compiled into PHP or dynamically loaded at runtime.