php - 列中值的 MySQL 计数

Question

我有一个列 package 并包含包 ID 1, 2, 3, 4。现在我的查询将选择所有表 stores_profile 和 stores_fee 并按 date 过滤并按 month

下面是我的数据库:

表:stores_profile

表:stores_fee

这是我当前的查询:

<?php
$filter_date = '2013-04-01';

$result = mysql_query("SELECT sp.*, sf.*, sp.id as store_profile_id,DATE_FORMAT(sf.date_start, '%d-%m-%Y') as month
 FROM `stores_profile` sp
 left join `stores_fee` sf ON sp.id=sf.store_id 
 where sf.date_start >= '".$filter_date."' GROUP BY MONTH(sf.date_start) ");

while($row = mysql_fetch_array($result)) {
    $month = date('M', strtotime($row['month']));
    $package = $row['package']; 
?>
      <tr>
        <td><?php echo $month ?>&nbsp;</td>
        <td>&nbsp;</td>
        <td>&nbsp;</td>
        <td>&nbsp;</td>
        <td>&nbsp;</td>
      </tr>
<?php } echo '</table>'; ?>

这段代码的结果是:

那么，如何计算 package 列中的包 id，然后按月分组并根据包 id 获得总数，我知道这有点令人困惑，但结果应该如下所示:

Answer 1

您可以尝试使用 SUM 和 CASE:

SELECT DATE_FORMAT(sf.date_start, '%d-%m-%Y') as `Month`,
       SUM(CASE WHEN sf.package = 1 THEN 1 ELSE 0 END) AS `Package 1`,
       SUM(CASE WHEN sf.package = 2 THEN 1 ELSE 0 END) AS `Package 2`,
       SUM(CASE WHEN sf.package = 3 THEN 1 ELSE 0 END) AS `Package 3`,
       SUM(CASE WHEN sf.package = 4 THEN 1 ELSE 0 END) AS `Package 4`
FROM `stores_profile` sp
LEFT JOIN `stores_fee` sf ON sp.id = sf.store_id 
WHERE sf.date_start >= '".$filter_date."' GROUP BY MONTH(sf.date_start)

我能想到的另一种方法是对其进行子查询。