如何通過PHP檢索COUNT（*）語句的結果

Question

如何使用PHP檢索以下COUNT（*）MYSQL語句的結果？

MYSQL

$sql= mysql_query ("
                    select count(*)
                    from orders o
                    WHERE order_status IN
                    ('Printed Order', 'Charged Order', 'Exchanged Order', 'Refunded Order', 'Cancelled Order')
                    GROUP BY FIELD
                    (order_status,'Printed Order', 'Charged Order', 'Exchanged Order', 'Refunded Order', 'Cancelled Order')
                  ");

以上查詢結果

count(*)
226
19130
593
2603
2892

我嘗試了以下代碼按順序檢索每一行-

PHP

$row = mysql_fetch_row($sql);
echo $row[0];
echo $row[1];
echo $row[2];
echo $row[3];
echo $row[4];

產生以下錯誤： Notice: Undefined offset: 1 ...

我知道我缺少了一些非常簡單的東西，但是請有人告訴我調用COUNT（*）查詢結果的正確方法。

Answer 1

您的查詢返回5行。 您必須遍歷它們並顯示列：

while($row = mysql_fetch_row($sql)){
    echo $row[0];
}

另請參閱文檔

使用別名進行計數也很有意義。

$sql= mysql_query = "
                    select count(*) as countValue
                    from orders o
                    WHERE order_status IN
                    ('Printed Order', 'Charged Order', 'Exchanged Order', 'Refunded Order', 'Cancelled Order')
                    GROUP BY FIELD
                    (order_status,'Printed Order', 'Charged Order', 'Exchanged Order', 'Refunded Order', 'Cancelled Order')
                  ";

while($row = mysql_fetch_row($sql)){
    echo $row["countValue"];
}

警告：從PHP 5.5.0開始不推薦使用mysql_擴展名，以后會刪除它。 相反，應使用MySQLi或PDO_MySQL擴展。

Answer 2

您需要添加循環以獲取所有數據並使用mysqli而不是mysql。

像這樣的東西

 $sql= "select count(*) as total from orders o WHERE order_status IN
       ('Printed Order', 'Charged Order', 'Exchanged Order', 'Refunded Order', 'Cancelled Order') GROUP BY FIELD (order_status,'Printed Order', 'Charged Order', 'Exchanged Order', 'Refunded Order', 'Cancelled Order')"

$result = mysqli_query($con, $sql);

while($row = mysqli_fetch_array($result)) {
   echo $row['total'];
   echo "<br>";
}

您也可以對mysql而不是mysqli使用相同的方法，但是mysqli對於將來的使用會更好。

$result = mysql_query($sql);

while($row = mysql_fetch_row($sql)){
   echo $row['total'];
   echo "<br>";
}

Answer 3

$sql= mysql_query ("
                    select count(*) as nbre
                    from orders o
                    WHERE order_status IN
                    ('Printed Order', 'Charged Order', 'Exchanged Order', 'Refunded Order', 'Cancelled Order')
                    GROUP BY FIELD
                    (order_status,'Printed Order', 'Charged Order', 'Exchanged Order', 'Refunded Order', 'Cancelled Order')
                  ");


echo $row[0]['nbre'];