Question

我想知道我的Stack Overflow声誉排除在询问和回答regex问题时获得或失去的所有声誉（对我而言，感觉就像“脏钱”！）

Stack Exchange的Data Explorer将允许我计算这个。但是，我只使用专有数据库和C ++包装类编程，所以我对我的SQL技能不太自信。尽管如此，我还是试了一下，最终提出了a query that provided my answer：

-- (approximate) reputation gained/lost on a specified tag
-- only counts post upvotes and downvotes

DECLARE @UserId        int = ##UserId##
DECLARE @QuestionsUp   int = 0;
DECLARE @QuestionsDown int = 0;
DECLARE @AnswersUp     int = 0;
DECLARE @AnswersDown   int = 0;
DECLARE @Tag           nvarchar(25) = 'regex';

SELECT
    @QuestionsUp = COUNT(*)
FROM Tags
    INNER JOIN PostTags ON PostTags.TagId = Tags.id
    INNER JOIN Posts ON Posts.ParentId = PostTags.PostId
    INNER JOIN Votes ON Votes.PostId = Posts.Id and VoteTypeId = 2
WHERE 
    Posts.OwnerUserId = @UserId and
    Posts.PostTypeId = 1 and
    Tags.TagName = @Tag

SELECT
    @QuestionsDown = COUNT(*)
FROM Tags
    INNER JOIN PostTags ON PostTags.TagId = Tags.id
    INNER JOIN Posts ON Posts.ParentId = PostTags.PostId
    INNER JOIN Votes ON Votes.PostId = Posts.Id and VoteTypeId = 3
WHERE 
    Posts.OwnerUserId = @UserId and
    Posts.PostTypeId = 1 and
    Tags.TagName = @Tag

SELECT
    @AnswersUp = COUNT(*)
FROM Tags
    INNER JOIN PostTags ON PostTags.TagId = Tags.id
    INNER JOIN Posts ON Posts.ParentId = PostTags.PostId
    INNER JOIN Votes ON Votes.PostId = Posts.Id and VoteTypeId = 2
WHERE 
    Posts.OwnerUserId = @UserId and
    Posts.PostTypeId = 2 and
    Tags.TagName = @Tag

SELECT
    @AnswersDown = COUNT(*)
FROM Tags
    INNER JOIN PostTags ON PostTags.TagId = Tags.id
    INNER JOIN Posts ON Posts.ParentId = PostTags.PostId
    INNER JOIN Votes ON Votes.PostId = Posts.Id and VoteTypeId = 3
WHERE 
    Posts.OwnerUserId = @UserId and
    Posts.PostTypeId = 2 and
    Tags.TagName = @Tag

SELECT @QuestionsUp * 5 +
       @AnswersUp * 10 +
       (@QuestionsDown + @AnswersDown) * -2

但这不是最好的。四个单独的查询只是为了将问题的评分加权5，将评价的评分提高10，将问题和答案的评分提高到-2？有没有办法压缩这个查询以便在一次运行中执行？

（如果您对语法，格式，良好做法等有任何辅助建议，请随时发表评论。另外，如果还有其他方法可以获得或失去特定于标签的声誉，请发表评论 - 我还没有考虑到了。）

Answer 1

你可以尝试像

这样的东西

SELECT
    SUM(
        CASE
            WHEN VoteTypeId = 2 AND Posts.PostTypeId = 1
                THEN 1
            ELSE 0
        END
    )   QuestionsUp,
    SUM(
        CASE
            WHEN VoteTypeId = 3 AND Posts.PostTypeId = 1
                THEN 1
            ELSE 0
        END
    )   QuestionsDown,
    SUM(
        CASE
            WHEN VoteTypeId = 2 AND Posts.PostTypeId = 2
                THEN 1
            ELSE 0
        END
    )   AnswersUp,
    SUM(
        CASE
            WHEN VoteTypeId = 3 AND Posts.PostTypeId = 2
                THEN 1
            ELSE 0
        END
    )   AnswersDown
FROM Tags
    INNER JOIN PostTags ON PostTags.TagId = Tags.id
    INNER JOIN Posts ON Posts.ParentId = PostTags.PostId
    INNER JOIN Votes ON Votes.PostId = Posts.Id 
WHERE 
    Posts.OwnerUserId = @UserId and
    Tags.TagName = @Tag

修改

您可以使用CTE，然后使用计算中的列。

像
这样的东西
;WITH Vals AS ( SELECT SUM( CASE WHEN VoteTypeId = 2 AND Posts.PostTypeId = 1 THEN 1 ELSE 0 END ) QuestionsUp, SUM( CASE WHEN VoteTypeId = 3 AND Posts.PostTypeId = 1 THEN 1 ELSE 0 END ) QuestionsDown, SUM( CASE WHEN VoteTypeId = 2 AND Posts.PostTypeId = 2 THEN 1 ELSE 0 END ) AnswersUp, SUM( CASE WHEN VoteTypeId = 3 AND Posts.PostTypeId = 2 THEN 1 ELSE 0 END ) AnswersDown FROM Tags INNER JOIN PostTags ON PostTags.TagId = Tags.id INNER JOIN Posts ON Posts.ParentId = PostTags.PostId INNER JOIN Votes ON Votes.PostId = Posts.Id WHERE Posts.OwnerUserId = @UserId and Tags.TagName = @Tag ) SELECT QuestionsUp * 5 + AnswersUp * 10 + (QuestionsDown + AnswersDown) * -2 FROM Vals

有没有办法根据WHERE表达式计算权重加权和？

1 个答案: