$avg_pgt = mysql_query("SELECT avg(convert(custom_var_v1,unsigned)),min(convert(custom_var_v1,unsigned)), max(convert(custom_var_v1,unsigned) FROM `table_name` WHERE server_time BETWEEN '$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布尔值