Introduction
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.
Requirements
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:
Documentation for adding additional database support to dbx can be
found at http://www.guidance.nl/php/dbx/doc/.
Installation
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.
Runtime Configuration
The behaviour of these functions is affected by settings in php.ini.
Table 1. DBX Configuration Options
| Name | Default | Changeable |
|---|
| dbx.colnames_case | "unchanged" | PHP_INI_SYSTEM |
For further details and definition of the PHP_INI_* constants see
ini_set().
Note:
This ini-option is available available from PHP 4.3.0.
Here's a short explanation of
the configuration directives.
- dbx.colnames_case
string
Columns names can be returned "unchanged" or converted to
"uppercase" or "lowercase". This directive can be overridden
with a flag to dbx_query().
Resource Types
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.
Predefined Constants
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.