PHP调用存储过程返回值不一致问题的解决方法分析

delimiter//
createprocedureusp_s2(outpar1int)
begin
selectinet_ntoa(ip),portfromproxy_listlimit5;
selectcount(*)intopar1fromproxy_list;
END//
delimiter;

mysql>callusp_s2(@a);
+—————+——+
|inet_ntoa(ip)|port|
+—————+——+
|1.34.21.86  |8088|
|1.34.59.50  |8088|
|1.34.69.15  |8088|
|1.34.73.110  |8088|
|1.34.76.218  |8088|
+—————+——+
5rowsinset(0.00sec)
QueryOK,1rowaffected(0.01sec)
mysql>select@a;
+——+
|@a  |
+——+
|4430|
+——+
1rowinset(0.00sec)

mysql>select@a;
+——+
|@a  |
+——+
|NULL|
+——+
1rowinset(0.00sec)

<?php
$hostname="127.0.0.1";
$username="wubx";
$password="wubxwubx";
$database="proxydb";
$db=newmysqli($hostname,$username,$password,$database);
if(mysqli_connect_errno()){
    printf("Connect failed: %s\n",mysqli_connect_error());
    exit();
}
$result=$db->multi_query("call usp_s2(@total); select @total;");
if($result){
    do{
    if($r=$db->store_result()){
        if($r->field_count==2){
            while($row=$r->fetch_row()){
                print"ip: $row[0], port: $row[1]\n";
            }
        }else{
            $row =$r->fetch_row();
            print"total: $row[0]\n";
        }
    }
    }while($db->next_result());
}
$db->close();
?>