I use this query to
SELECT userId, submDate, COUNT(submId) AS nSubms
FROM submissions
GROUP BY userId, submDate
ORDER BY userId, submDate
obtain the total number of submissions per user per date.
However I need to have the progressive count for every user so I can see how their submissions accumulate over time.Is this possible to implement in a query ?
EDIT: The obtained table looks like this :
userId submDate nSubms
1 2-Feb 1
1 4-Feb 7
2 1-Jan 4
2 2-Jan 2
2 18-Jan 1
I want to produce this :
userId submDate nSubms progressive
1 2-Feb 1 1
1 4-Feb 7 8
2 1-Jan 4 4
2 2-Jan 2 6
2 18-Jan 1 7
EDIT 2 : Sorry for not mentioning it earlier, I am not allowed to use :
Stored procedure calls
Update/Delete/Insert/Create queries
Unions
DISTINCT keyw开发者_如何学Cord
as I am using a tool that doesn't allow those.
You can use a self-join to grab all the rows of the same table with a date before the current row:
SELECT s0.userId, s0.submDate, COUNT(s0.submId) AS nSubms, COUNT (s1.submId) AS progressive
FROM submissions AS s0
JOIN submissions AS s1 ON s1.userId=s0.userId AND s1.submDate<=s0.submDate
GROUP BY s0.userId, s0.submDate
ORDER BY s0.userId, s0.submDate
This is going to force the database to do a load of pointless work counting all the same rows again and again though. It would be better to just add up the nSubms
as you go down in whatever script is calling the query, or in an SQL variable, if that's available in your environment.
The Best solution for this is to do it at the client.
It's the right tool for the job. Databases are not suited for this kind of task
Select S.userId, S.submDate, Count(*) As nSubms
, (Select Count(*)
From submissions As S1
Where S1.userid = S.userId
And S1.submDate <= S.submDate) As TotalSubms
From submissions As S
Group By S.userid, S.submDate
Order By S.userid, S.submDate
精彩评论