mysql_free_result() Function for PHP
What is mysql_free_result() function in PHP?
How does mysql_free_result() works?
Explanation
Mysql function
mysql_free_result() will free all memory associated with the result identifier result.
Syntaxbool mysql_free_result ( resource result)
This mysql_free_result() returns TRUE on success, or FALSE on failure.
mysql_free_result() frees the memory used by a result handle, deleting the result handle in the process. 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. In most cases, this function is unnecessary; PHP's memory-management system automatically releases the memory used by result handles at the end of the script execution.
Example:
<?php //Attempt to connect to the default database server $link = mysql_connect("mysql_host", "mysql_user", "mysql_password") or die ("Could not connect"); //select database mysql_select_db("my_database"); //execute simple query $result = mysql_query("SELECT * FROM mytable"); $row = mysql_fetch_array($result,MYSQL_BOTH); //print result print_r($row); //free the result resource mysql_free_result($result); ?> |
RESULT:
Array (
[0] => 76 [id] => 76
[1] => Nicolus [name] => Nicolus
[2] => selected [status] => selected
)
In the above code mysql_free_result() function is used to free the result handle '$result'. When the result handle is accessed after deleting the result resource using mysql_free_result() function will result in error.
Example:
<?php //Attempt to connect to the default database server $link = mysql_connect("mysql_host", "mysql_user", "mysql_password") or die ("Could not connect"); //select database mysql_select_db("my_database"); //execute simple query $result = mysql_query("SELECT * FROM mytable"); $row = mysql_fetch_array($result,MYSQL_BOTH); //print result print_r($row); //free the result resource mysql_free_result($result); $row = mysql_fetch_array($result,MYSQL_BOTH); //print result print_r($row); ?> |
RESULT:
mysql_fetch_array(): is not a valid MySQL result resource