PHP Manual: Performs debugging operations

Description

Object-oriented style

public true mysqli::debug(string $options)

Procedural style

true mysqli_debug(string $options)

Performs debugging operations using the Fred Fish debugging library.

Parameters

options

A string representing the debugging operation to perform

The debug control string is a sequence of colon separated fields as follows:

<field_1>:<field_2>:<field_N>

Each field consists of a mandatory flag character followed by an optional , and comma separated list of modifiers: flag[,modifier,modifier,...,modifier]

**Recognized Flag Characters**
`options` character	Description
O	`MYSQLND_DEBUG_FLUSH`
A/a	`MYSQLND_DEBUG_APPEND`
F	`MYSQLND_DEBUG_DUMP_FILE`
i	`MYSQLND_DEBUG_DUMP_PID`
L	`MYSQLND_DEBUG_DUMP_LINE`
m	`MYSQLND_DEBUG_TRACE_MEMORY_CALLS`
n	`MYSQLND_DEBUG_DUMP_LEVEL`
o	output to file
T	`MYSQLND_DEBUG_DUMP_TIME`
t	`MYSQLND_DEBUG_DUMP_TRACE`
x	`MYSQLND_DEBUG_PROFILE_CALLS`

Return Values

Always returns true.

Changelog

Version	Description
8.0.0	This function now always returns `true`. Previously it returned `false` on failure.

Examples

Example #1 Generating a Trace File

<?php

/* Create a trace file in '/tmp/client.trace' on the local (client) machine: */
mysqli_debug("d:t:o,/tmp/client.trace");

?>

Notes

Note:
To use the mysqli_debug function you must compile the MySQL client library to support debugging.

mysqli::debug

mysqli_debug