使用多个表中的计算创建SQL视图

Question

So I have two tables that I need information from. I have a ballot_table(vote CHAR(30), username CHAR(30)) that has the name of the candidate each username voted for. I also have another table with a list of the candidates. I need someway to return the list of candidates with the corresponding amount of times there name appears in ballot_table in the same query. Thanks!

Answer 1

This is a horrible design but here is how you do it:

   select count(*) as votes, vote as [candidate]
   from ballot_table
   where ucase(vote) in (select ucase(item) from table_with_list_of_candidates)
   group by ucase(vote)

a better design would have the list of candidates table include a key and then just have the key in the ballot_table with a varchar for a write in (if needed).

Answer 2

You can do this with an Outer Join and a Group By . I'm assuming the field name in the candidate table is Name .

Select      c.Name, Count(Distinct b.UserName) Votes
From        ballot_table    b
Right Join  candidate       c On c.Name = b.Vote
Group By    c.Name

This would only return the total votes for the candidates you have in your Candidate table. Any other "write-in" vote wouldn't be included.