XXI. dbx functions

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, following databases are supported, but others will follow:

FrontBase (available from PHP 4.1.0).
Microsoft SQL Server
MySQL
ODBC
PostgreSQL
Sybase-CT (available from PHP 4.2.0).
Oracle (oci8) (available from PHP 4.3.0).

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 is 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 helds 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.

DBX_MYSQL (integer)
DBX_ODBC (integer)
DBX_PGSQL (integer)
DBX_MSSQL (integer)
DBX_FBSQL (integer)
DBX_OCI8 (integer) (available from PHP 4.3.0)
DBX_SYBASECT (integer)
DBX_PERSISTENT (integer)
DBX_RESULT_INFO (integer)
DBX_RESULT_INDEX (integer)
DBX_RESULT_ASSOC (integer)
DBX_COLNAMES_UNCHANGED (integer) (available from PHP 4.3.0)
DBX_COLNAMES_UPPERCASE (integer) (available from PHP 4.3.0)
DBX_COLNAMES_LOWERCASE (integer) (available from PHP 4.3.0)
DBX_CMP_NATIVE (integer)
DBX_CMP_TEXT (integer)
DBX_CMP_NUMBER (integer)
DBX_CMP_ASC (integer)
DBX_CMP_DESC (integer)

Table of Contents
dbx_close?--?Close an open connection/database
dbx_compare?--?Compare two rows for sorting purposes
dbx_connect?--?Open a connection/database
dbx_error?--? Report the error message of the latest function call in the module (not just in the connection)
dbx_escape_string?--? Escape a string so it can safely be used in an sql-statement.
dbx_query?--?Send a query and fetch all results (if any)
dbx_sort?--? Sort a result from a dbx_query by a custom sort function