Overview
KB
Technical FAQ
PHP Manual
CSS2 Manual
HTML Manual
JS Guide
JS Reference
PhpDock Manual
Nu-Coder Manual
PhpExpress Manual
PHP Joomla
Development
Learn PHP
 
<oci_pconnectoci_result>
^OCI8 FunctionsLast updated: Mon, 26 Oct 2026

oci_register_taf_callback

(PHP 7.0 >= 7.0.21, PHP 8, PHP 7 >= 7.1.7, PHP 8, PECL OCI8 >= 2.1.7)

oci_register_taf_callback — Register a user-defined callback function for Oracle Database TAF

Description

function oci_register_taf_callback(resource $connection, ?callable $callback): bool

Registers a user-defined callback function to connection. If connection fails due to instance or network failure, the registered callback function will be invoked for several times during failover. See OCI8 Transparent Application Failover (TAF) Support for information.

When oci_register_taf_callback() is called multiple times, each registration overwrites the previous one.

Use oci_unregister_taf_callback() to explicitly unregister a user-defined callback.

TAF callback registration will NOT be saved across persistent connections, therefore the callback needs to be re-registered for a new persistent connection.

Parameters

connection

An Oracle connection identifier.

callback

A user-defined callback to register for Oracle TAF. It can be a string of the function name or a Closure (anonymous function).

The interface of a TAF user-defined callback function is as follows:

function userCallbackFn(resource $connection, int $event, int $type): int

See the parameter description and an example on OCI8 Transparent Application Failover (TAF) Support page.

Return Values

Returns true on success or false on failure.

See Also


<oci_pconnectoci_result>
^OCI8 FunctionsLast updated: Mon, 26 Oct 2026