PHP mysqli $error Property

The PHP mysqli::$error / mysqli_error() function returns the last error message for the most recent MySQLi function call that can succeed or fail.

Syntax

//Object-oriented style
$mysqli->error;

//Procedural style
mysqli_error(mysql)

Parameters

mysql Required. For procedural style only: Specify a mysqli object returned by mysqli_connect() or mysqli_init().

Return Value

Returns a string that describes the error. An empty string if no error occurred.

Example: Object-oriented style

The example below shows the usage of mysqli::$error property.

<?php
//establishing connection to the database
$mysqli = new mysqli("localhost", "user", "password", "database");
if ($mysqli->connect_errno) {
  echo "Failed to connect to MySQL: ". $mysqli->connect_error;
  exit();
}

//executing an SQL query
$sql = "SET x=1";

if (!$mysqli->query($sql)) {
  printf("Error message: %s\n", $mysqli->error);
}

//closing the connection
$mysqli->close();
?>

The output of the above code will be similar to:

Error message: Unknown system variable 'x'

Example: Procedural style

The example below shows the usage of mysqli_error() function.

<?php
//establishing connection to the database
$mysqli = mysqli_connect("localhost", "user", "password", "database");
if (mysqli_connect_errno()) {
  echo "Failed to connect to MySQL: ". mysqli_connect_error();
  exit();
}

//executing an SQL query
$sql = "SET x=1";

if (!mysqli_query($mysqli, $sql)) {
  printf("Error message: %s\n", mysqli_error($mysqli));
}

//closing the connection
mysqli_close($mysqli);
?>

The output of the above code will be similar to:

Error message: Unknown system variable 'x'

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