从SQL输出中仅读取一列作为PHP中的数值数组 [英] Reading only one column from SQL output as a numerical array in PHP

问题描述

我运行以下查询：

  SELECT tagID, 
         COUNT(*) AS TotalOccurrences
    FROM coupon_tags
GROUP BY tagID
ORDER BY TotalOccurrences DESC 
   LIMIT 10

它返回这样的输出：

tagID  TotalOccurrences 
------------------------
7      9
2      8
1      3
6      2
3      1
4      1
5      1
8      1

我不能做 mysql_fetch_array（mysql_query（$ thatQuery）; ，因为它有两列数据，而任何数组都被拖拉了，就像垃圾一样。我如何进一步简化该查询，使它仍然是一列仍然排序的数据，所以更容易在数组中使用？或者也许我使用了错误的PHP / MySQL函数（尽管我仔细检查了所有内容）？

I can't do a mysql_fetch_array(mysql_query($thatQuery); because it has two columns of data and any array pulled looks like garbage. How can I further streamline that query to a single column of still-sorted data, so it's easier to work with in an array? Or maybe I am using the wrong PHP/MySQL function (although I looked through them all)?

编辑：我发现查询在phpMyAdmin中可以正常工作，但是当我尝试使用phpMyAdmin查询时失败 mysql_query（）。

I've found out that the query will work fine in phpMyAdmin but it fails when I try to query with mysql_query().

我的php代码：

$tagSQL = mysql_query($selectorSQL);
        if (!$tagSQL) die("query failed");  //fails here
            while ($tSrow = mysql_fetch_assoc($tagSQL)) {
                var_dump($tSrow);
            }

推荐答案

您可以这样做将查询简化为仍然排序的数据的单列。

You can do it like this to "streamline that query to a single column of still-sorted data".

SELECT tagID            
FROM coupon_tags
GROUP BY tagID
ORDER BY COUNT(tagID) DESC 
LIMIT 10

只需确保对单个列使用计数，而不要对所有内容进行计数，这将极大地影响性能。

Just make sure to use count on a single column instead of counting everything, this will greatly affect performance.

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