Question

This does not work

    $get_data_qry   = "SELECT * FROM list;";
    $get_data_res   = $db->Query($get_data_qry);

    $key           = 'someKey';  /** silly mistake corrected after being notified by comments*/
    $get_data_res   = $memcache->get($key);

    if ($get_data_res) {
        PushOutput($get_data_res);
        echo "<br/>Directly from cache";
    }

    else {
        $get_data_res   = $db->Query($get_data_qry);
        $memcache->set($key, $get_data_res, 0, 20000);  /*Store the MySql resource in the cache*/
        PushOutput($get_data_res);
    }

I get the following message: PHP Warning: Memcache::set() expects parameter 1 to be string, resource given in E:\Repository\HTML\tooldent\songs\songList.tpl on line 54.

It seems weird, why a resource cannot be cached? Any alternatives?

Answer 1

If your $db construct use mysql_query:

For SELECT, SHOW, DESCRIBE, EXPLAIN and other statements returning resultset, mysql_query() returns a resource on success.

A resultset is not a string and you set $key to the resultset at line 4.

Update:

$result = $db->query( "SELECT * FROM table" );
$memcache->set(1,$result,TRUE,86400) or die ("Failed to save data");
$cached_result = $memcache->get(1);
var_dump($cached_result);

Output:

object(mysql_result)#2 (0) { }

But as far as I know you can’t treat this object as a normal mysql object:

 mysql_fetch_assoc($cached_result)

You can try to create a multidimensional array out of the resultset for memcache.