mysql_query() also returns a resource for "OPTIMIZE TABLE" statements!
mysql_free_result
(PHP 4, PHP 5)
mysql_free_result — Free result memory
Увага
This extension is deprecated as of PHP 5.5.0, and will be removed in the future. Instead, the MySQLi or PDO_MySQL extension should be used. See also MySQL: choosing an API guide and related FAQ for more information. Alternatives to this function include:
- mysqli_free_result()
- Assign the value of
NULLto the PDO object, or PDOStatement::closeCursor()
Опис
bool mysql_free_result
( resource
$result
)
mysql_free_result() will free all memory
associated with the result identifier result.
mysql_free_result() only needs to be called if you are concerned about how much memory is being used for queries that return large result sets. All associated result memory is automatically freed at the end of the script's execution.
Параметри
-
result -
The result resource that is being evaluated. This result comes from a call to mysql_query().
Значення, що повертаються
Повертає TRUE в успішному випадку або FALSE в разі помилки.
If a non-resource is used for the result, an
error of level E_WARNING will be emitted. It's worth noting that
mysql_query() only returns a resource
for SELECT, SHOW, EXPLAIN, and DESCRIBE queries.
Приклади
Приклад #1 A mysql_free_result() example
<?php
$result = mysql_query("SELECT id,email FROM people WHERE id = '42'");
if (!$result) {
echo 'Could not run query: ' . mysql_error();
exit;
}
/* Use the result, assuming we're done with it afterwards */
$row = mysql_fetch_assoc($result);
/* Now we free up the result and continue on with our script */
mysql_free_result($result);
echo $row['id'];
echo $row['email'];
?>
Примітки
Зауваження:
Для зворотньої сумісності, можна використовувати наступний застарівший псевдонім: mysql_freeresult()
Прогляньте Також
- mysql_query() - Send a MySQL query
- is_resource() - Finds whether a variable is a resource
add a note
User Contributed Notes 3 notes
webmaster at bluesting dot co dot za ¶
13 years ago
admin at ifyouwantblood dot de ¶
16 years ago
yes this function may increase the memory usage if you use unbuffered querys and if you have not fetched all the data from mysql. in this case the mysql api has a problem: you want to free the result but do not want to close the connection. now mysql will only accept another query if all data has been fetched, so the api now must fetch the rest of the data when calling mysql_free_result().
so only use unbuffered querys if you fetch all the data (and need it).
