Question

我正在尝试从JIRA应用程序查询多个表，我们正在运行Oracle DB。我试图做的是写一个单一的查询，可以总计用户名的数量和它看到的单个用户名的次数。我可以在每个统计基础上做这个（评论，问题历史等等），但还没有找到一种能够以有意义的方式组合我的查询的方法....

-- Comment total by user query:
select author, count(actiontype) as total
from jiraaction 
group by author
order by total desc;
-- Jira issues reported by user query:
select reporter, count(reporter) as total
from jiraissue
group by reporter
Order by total desc

Answer 1

使用union all并重新组合：

select author, sum(authors) as NumAuthors, sum(Reporters) as NumReporters,
       (sum(authors) + sum(reporters) ) as Total
from ((select author, count(actiontype) as authors, 0 as reporters
       from jiraaction 
       group by author
      ) union all
      (select reporter, 0, count(reporter)
       from jiraissue
       group by reporter
      )
     ) ar
group by author
Order by total desc;

Answer 2

您可以使用UNION操作。像这样：

Select a.author, sum(a.total) as total
  from ( 
         select author, count(actiontype) as total
           from jiraaction 
          group by author
          UNION ALL
         select reporter, count(reporter) as total
           from jiraissue
          group by reporter
        ) a
 order by a.total desc

SQL查询具有包含相同数据的不同列名的多个表

2 个答案: