mysql - 按集合中最多标签排序

Question

SqlCommand sqlcmd = new SqlCommand("SELECT  Username, TimesUsed FROM  UserInfo " +
           "WHERE  (Category IN ( " + query + ")) " + "ORDER BY TimesUsed DESC", conn);

其中 query = 'css','php','html' 例如

我想以这样的方式对它们进行排序，即在查询中拥有最多标签的用户被放置在顶部。

目前，它们是根据使用集合中特定标签的次数进行排序的。

有什么想法吗？预先感谢:)

Answer 1

所以，如果我理解的话，您需要使用的所有标签的总数，而 TimesUsed 与特定标签相关。如果这是正确的，那么您可以 SUM(TimesUsed) 和 GROUP BY Username

SqlCommand sqlcmd = new SqlCommand("SELECT  Username, SUM(TimesUsed) AS TotalUsed FROM  UserInfo " +
       "WHERE  (Category IN ( " + query + ")) " + "GROUP BY Username ORDER BY SUM(TimesUsed) DESC", conn);
        sqlcmd.Parameters.AddWithValue("@c", query);

您的完整 SQL:

SELECT
  Username, 
  SUM(TimesUsed) AS TotalUsed
FROM  UserInfo
WHERE Category IN ('php','css','sql','etc')
GROUP BY Username
ORDER BY SUM(TimesUsed) DESC