ezSQL abnormal behaviour

Question

I am using ezSQL for database queries and connection and sometimes it gives data and sometimes it return no results.

Here is the debug code

Query [3] -- [SELECT * FROM table WHERE `id`=4]
Query Result..

No Results

CODE:

public function select($table, $rows = '*', $where = null,$datatype = 'results') {
        global $db;
        $q = 'SELECT ' . $rows . ' FROM ' . $table;
        if ($join != null) {
            $q .= ' JOIN ' . $join;
        }
        if ($where != null) {
            $q .= ' WHERE ' . $where;
        }
        self::prt_debug("db", $db );
        self::prt_debug("SELECT Query", $q );
        if ($datatype == 'row')
            $results = $db->get_row ( $q );
        else
            $results = $db->get_results ( $q );
        $db->debug();
        return $results;
}

The query is very simple, but it gives data sometimes only.

Can anyone have the idea about it?

I have tried to use ob_start() function on page start so if any cache or buffer it clears but doesn't work

Thanks,