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PHP MySQLi: debug() function

mysqli_debug() function / mysqli::debug

The mysqli_debug() function / mysqli::debug is used to perform debugging operations.

Note: In order to use this function, you must compile the MySQL client library to support debugging.

Syntax:

Object oriented style

bool mysqli::debug ( string $message )

Procedural style

bool mysqli_debug ( string $message )

Usage: Procedural style

mysqli_debug(message);

Parameter:

Name Description Required/Optional
massage A string that represents the debugging operation to perform Required

Return value:

Returns TRUE.

Version: PHP 5, PHP 7

Example:

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

See also

PHP Function Reference

Previous: connect
Next: dump_debug_info



PHP: Tips of the Day

var_export(): var_export() dumps a PHP parseable representation of the item.

You can pass true as the second parameter to return the contents into a variable.

Example:

<?php
$myarray = [ "PHP", "Tips" ];
$mystring = "PHP Tips";
$myint = 28;

var_export($myarray);
var_export($mystring);
var_export($myint);
?>

Output:

array (
  0 => 'PHP',
  1 => 'Tips',
)'PHP Tips'28

To put the content into a variable, you can do this:

$array_export = var_export($myarray, true);
$string_export = var_export($mystring, true);
$int_export = var_export($myint, 1); // any `Truthy` value

After that, you can output it like this:

printf('$myarray = %s; %s', $array_export, PHP_EOL);
printf('$mystring = %s; %s', $string_export, PHP_EOL);
printf('$myint = %s; %s', $int_export, PHP_EOL);

Example:

<?php
$myarray = [ "PHP", "Tips" ];
$mystring = "PHP Tips";
$myint = 28;
$array_export = var_export($myarray, true);
$string_export = var_export($mystring, true);
$int_export = var_export($myint, 1);
printf('$myarray = %s; %s', $array_export, PHP_EOL);
printf('$mystring = %s; %s', $string_export, PHP_EOL);
printf('$myint = %s; %s', $int_export, PHP_EOL);
?>

This will produce the following output:

Output:

$myarray = array (
  0 => 'PHP',
  1 => 'Tips',
);
$mystring = 'PHP Tips';
$myint = 28;