Question

所以我在MySQL数据库中有两列文本，例如：

Name             Score
Henry Hodgens    4
Mary Hodgens     8
Jim Servan       2
Jane Servan      4
Hank Servan      6
Sarah Smith      10
Mary Smith       12
Henry Dobbins    2
Henry Jenkins    4

我需要使用PHP运行查询，该查询可以根据“名称”中单个单词的最常见情况显示“得分”的平均值。因此，它表明“Servan”平均为4，“Henry”平均为3.3，“Hodgens”平均为6，“Mary”平均为10，按“名称”中大多数出现的顺序排列。

我希望这是有道理的。

Answer 1

这在MySQL内部很难做到。它非常适合存储和检索关系值，而不是很好地进行这种计算。如果您不介意在PHP中执行此操作，则可以使用以下代码来计算频率。

foreach ($rows as $row)
{
    foreach (explode(" ", $row['Name']) as $token)
    {
        $total[$token] += (int)$row['Score']; 
        $occurances[$token]++;
    }
}

// compute average by taking ($total[$token])/($occurances[$token])

Answer 2

你可以这样做：

SELECT
    AVG(t.Score) AS ScorceAvg,
    t.name
FROM
    (
        SELECT 
            SUBSTRING(Table1.Name,1,INSTR(Table1.Name, ' ')) AS name,
            Table1.Score
        FROM 
            Table1
        UNION ALL
        SELECT 
            SUBSTRING(Table1.Name,INSTR(Table1.Name, ' ')) AS name,
            Score
        FROM 
            Table1
    ) AS t
GROUP BY
    t.name

Answer 3

这是完美的事情

SELECT distinct
       SUBSTRING(NAME, LOCATE(' ',NAME)+1) as NameED,
      (select
       avg(score)
       from avgscore
       where NameED = SUBSTRING(NAME, LOCATE(' ',NAME)+1)) as Score
FROM avgscore

Answer 4

试试这个

SELECT sum(Score)/count(Name) as average FROM tablename where Name regexp "Mary";

如何在MySQL数据库中查找最常用的单词并平均第二列

4 个答案: