php - Mysql-php mysql_fetch_array()

Question

        $avg_pgt = mysql_query("SELECT avg(convert(custom_var_v1,unsigned)),min(convert(custom_var_v1,unsigned)), max(convert(custom_var_v1,unsigned) FROM `table_name` WHERE server_time BETWEEN '$date 00:00:00' AND '$date 23:59:59'");

        $row_all = mysql_fetch_array($avg_pgt);         
        $string_avg = (string)$row_all[0];      
        echo $string_avg;

它给出了一个错误mysql_fetch_array()期望参数1是代码中给出的资源 bool 值

Answer 1

max(convert(custom_var_v1,unsigned)

最后缺少一个)，这可以工作:

    $avg_pgt = mysql_query("SELECT avg(convert(custom_var_v1,unsigned)),min(convert(custom_var_v1,unsigned)), max(convert(custom_var_v1,unsigned)) FROM `table_name` WHERE server_time BETWEEN '$date 00:00:00' AND '$date 23:59:59'");

    $row_all = mysql_fetch_array($avg_pgt);         
    $string_avg = (string)$row_all[0];      
    echo $string_avg;