Escapes special characters in a string for use in an SQL statement, taking into account the current charset of the connection

mysqli::real_connect
mysqli::real_query
mysqli
PHP Manual

# mysqli::real_escape_string

# mysqli_real_escape_string

(PHP 5)

mysqli::real_escape_string -- mysqli_real_escape_string — Escapes special characters in a string for use in an SQL statement, taking into account the current charset of the connection

### Description

Object oriented style

string mysqli::escape_string ( string `$escapestr` )
string mysqli::real_escape_string ( string `$escapestr` )

Procedural style

string mysqli_real_escape_string ( mysqli `$link` , string `$escapestr` )

This function is used to create a legal SQL string that you can use in an SQL statement. The given string is encoded to an escaped SQL string, taking into account the current character set of the connection.

Caution

# Security: the default character set

The character set must be set either at the server level, or with the API function mysqli_set_charset() for it to affect mysqli_real_escape_string(). See the concepts section on character sets for more information.

### Parameters

`link`

  Procedural style only: A link identifier returned by mysqli_connect() or mysqli_init()

`escapestr`

  The string to be escaped.

  Characters encoded are NUL (ASCII 0), \n, \r, \, ', ", and Control-Z.

### Return Values

Returns an escaped string.

### Examples

Example #1 mysqli::real_escape_string() example

Object oriented style

`<?php
$mysqli = new mysqli("localhost", "my_user", "my_password", "world");
/* check connection */
if (mysqli_connect_errno()) {
printf("Connect failed: %s\n", mysqli_connect_error());
exit();
}
$mysqli->query("CREATE TEMPORARY TABLE myCity LIKE City");
$city = "'s Hertogenbosch";
/* this query will fail, cause we didn't escape $city */
if (!$mysqli->query("INSERT into myCity (Name) VALUES ('$city')")) {
printf("Error: %s\n", $mysqli->sqlstate);
}
$city = $mysqli->real_escape_string($city);
/* this query with escaped $city will work */
if ($mysqli->query("INSERT into myCity (Name) VALUES ('$city')")) {
printf("%d Row inserted.\n", $mysqli->affected_rows);
}
$mysqli->close();
?>`

Procedural style

`<?php
$link = mysqli_connect("localhost", "my_user", "my_password", "world");
/* check connection */
if (mysqli_connect_errno()) {
printf("Connect failed: %s\n", mysqli_connect_error());
exit();
}
mysqli_query($link, "CREATE TEMPORARY TABLE myCity LIKE City");
$city = "'s Hertogenbosch";
/* this query will fail, cause we didn't escape $city */
if (!mysqli_query($link, "INSERT into myCity (Name) VALUES ('$city')")) {
printf("Error: %s\n", mysqli_sqlstate($link));
}
$city = mysqli_real_escape_string($link, $city);
/* this query with escaped $city will work */
if (mysqli_query($link, "INSERT into myCity (Name) VALUES ('$city')")) {
printf("%d Row inserted.\n", mysqli_affected_rows($link));
}
mysqli_close($link);
?>`

The above examples will output:

    Error: 42000
    1 Row inserted.

### Notes

> Note:

> For those accustomed to using mysql_real_escape_string(), note that the arguments of mysqli_real_escape_string() differ from what mysql_real_escape_string() expects. The `link` identifier comes first in mysqli_real_escape_string(), whereas the string to be escaped comes first in mysql_real_escape_string().

### See Also

- mysqli_set_charset() - Sets the default client character set
- mysqli_character_set_name() - Returns the default character set for the database connection

mysqli::real_connect
mysqli::real_query
mysqli
PHP Manual