Question

如何使用PHP检索以下COUNT（*）MYSQL语句的结果？

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')
                  ");

以上查询的结果

count(*)
226
19130
593
2603
2892

我已尝试使用以下代码按顺序检索每一行 -

PHP

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

会产生以下错误：Notice: Undefined offset: 1 ...

我知道我遗漏了一些非常简单的东西，但有人请告诉我调用COUNT（*）查询结果的正确方法。

Answer 1

您的查询返回5行。你必须循环它们并显示列：

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

另请参阅documentation

使用计数的别名也是有意义的。

$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：自PHP 5.5.0起，不推荐使用mysql_扩展名，将来会将其删除。相反，应该使用MySQLi或PDO_MySQL扩展。

Answer 2

你需要添加循环来获取所有数据并使用mysqli而不是mysql。

类似这样的事情

 $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>";
}

您也可以使用与mysql相同的方法而不是mysqli，但mysqli将来会更好用。

$result = mysql_query($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'];

如何通过PHP检索COUNT（*）语句的结果

3 个答案: