Popular questions by view count

Question

I made this query to create a graph of a user's popular questions and the view count on that question. It allows for a minimum of 500 views, and a score of 3.

DECLARE @allowed_min_views INT = 500;
DECLARE @allowed_min_score INT = 3;

DECLARE @user_id INT = ##UserId:int?-1##;
DECLARE @min_views INT = ##MinimumViews:int?500##;
DECLARE @min_score INT = ##MinimumScore:int?3##;
DECLARE @question INT = 1;

IF (@min_views < @allowed_min_views)
BEGIN
  PRINT '@MinimumViews must be larger than 499.'
END

IF (@min_score < @allowed_min_score)
BEGIN
  PRINT '@MinimumScore must be larger than 2.'
END

IF (@min_views >= @allowed_min_views AND @min_score >= @allowed_min_score)
BEGIN
  SELECT
      ViewCount
    , Score
    FROM Posts WHERE
      PostTypeId = @question
      AND OwnerUserId = @user_id
      AND ViewCount >= @min_views
      AND Score >= @min_score
    ORDER BY ViewCount ASC;
END

Finally, here's some sample input (I'm using @Mat'sMug's user ID):

@user_id:   23788
@min_views: 500
@min_score: 7

Answer 1

Good things

You use good local variables, and you are consistent with your naming. The typical naming for T-SQL is using PascalCase, however there are no standards and snake_case or camelCase work just as good, as long as you are consistent (which you are).

You validate your values, although I am not quite sure why you chose 500 and 3 as arbitrary minimums (might be worth documenting).

---

Results are not very useful...

As written, your query returns this:

ViewCount Score 
--------- ----- 
571       10    
629       5     
685       6     
721       10    
728       11    
761       12    
840       25    
849       7     
870       17    
888       9     
1065      10
...

Which is all well and good, except, it doesn't give much information. Let's say we rewrite it a bit like this:

IF (@min_views >= @allowed_min_views AND @min_score >= @allowed_min_score)
BEGIN
  SELECT
      ViewCount
    , Score
    , [User Link] = @user_id
    , [Post Link] = Id
    , CreationDate
    , [Tags] = Tags
    FROM Posts 
    WHERE
      PostTypeId = @question
      AND OwnerUserId = @user_id
      AND ViewCount >= @min_views
      AND Score >= @min_score
    ORDER BY ViewCount DESC;
END

Notice I changed ORDER BY to DESC, I think it makes more sense to show highest first.

Then we get a more sensible result set, e.g.:

Answer 2

DECLARE @allowed_min_views INT = 500;
DECLARE @allowed_min_score INT = 3;

This feels very user unfriendly. What is the reasoning for this limit?

---

SELECT
    ViewCount
  , Score
  FROM Posts WHERE
    PostTypeId = @question
    AND OwnerUserId = @user_id
    AND ViewCount >= @min_views
    AND Score >= @min_score
  ORDER BY ViewCount ASC;

Most queries don't indent the FROM any farther than the SELECT and put the WHERE in its own line as well. Otherwise, this looks good to me.

Answer 3

I like symmetry. It's a bit off-putting to see PascalCase symbols (the column names in the SE tables) and snake_case symbols (your variables) mixed together. It would be better to adjust to the given style, and use PascalCase for your variables.

The variable @question is a bit misleading. It's not a "question", not even a "question id", it's actually the id of the question type. So @QuestionTypeId would be a more natural name.

Finally, the requirement of a user id is not very user friendly. Everybody knows @Mat's Mug but I doubt many people know that he also goes by 23788. Sure, it's not too hard to look that up, but it still takes a few clicks per user. It would be better to allow lookups by either user name or user id.