Question

我正在试图找出一个SQLquery。

我有一个包含team_id，ip_address和date_voted字段的投票数据表，我需要为每个team_id返回一个投票数，但只计算第一个在任何24小时内每个IP地址10行。

Answer 1

没有时间检查，但以下应该可以解决问题。

SELECT Yr, DoY, team_id, SUM(IF NbVote < 10, NbVote, 10) As FilteredVoteCount
FROM (
  SELECT YEAR(date_voted) AS Yr, DAYOFYEAR(date_voted) AS DoY, 
    team_id, 
    ip_address,
    COUNT(*) AS NbVotes
  FROM myTable
  -- WHERE here for some possible extra condition.
  GROUP BY YEAR(date_voted), DAYOFYEAR(date_voted), team_id, ip_address
)
GROUP BY Yr, DoY, team_id
ORDER BY Yr, DoY, team_id   -- or some other order may be desired.

Answer 2

假设：从给定的IP地址开始，只有团队的前10张投票（投票表中的每一行都是对team_id的投票）应计入给定日期。

所以这是每队每天的原始投票。

select team_id, vote_date, ip_address, count(*) as raw_vote_count
  from votes
 group by team_id, vote_date, ip_address

现在，使用它，使用CASE表达式将票数减少到不超过10：

select team_id, vote_date, ip_address,
       case when raw_vote_count > 10 
            then 10 
            else raw_vote_count 
        end as adjusted_vote_count
  from (select team_id, vote_date, ip_address, count(*) as raw_vote_count
          from votes
         group by team_id, vote_date, ip_address
       ) sub1

如果你想在白天获得总票数，那就是：

select team_id, sum(adjusted_vote_count)
  from (
       select team_id, vote_date, ip_address,
              case when raw_vote_count > 10 
                   then 10 
                   else raw_vote_count 
               end as adjusted_vote_count
         from (select team_id, vote_date, ip_address, count(*) as raw_vote_count
                 from votes
                group by team_id, vote_date, ip_address
              ) sub1
       )
 where date = :mydate
 group by team_id
 order by team_id

聚合具有要考虑的最大行数的SQL查询

2 个答案: