Solved

How do I group the filename coloumn so it is only showing 1 result row per filename?

Posted on 2011-02-22
2
366 Views
Last Modified: 2012-05-11
I need to group the distinct filenames. Currently there is a record for every instance of a filename.
select x.*, (SELECT ratingsum / filenamecount) as divnumber
from (
SELECT  filename, rating,
                          (SELECT     SUM(rating) AS Expr1
                            FROM        mytable AS GV
                            WHERE      GV.filename = a.filename) AS ratingsum,
                          (SELECT     COUNT(*) AS Expr2
                            FROM          mytable AS GV
                            WHERE       GV.filename = a.filename) AS filenamecount
                          
FROM         mytable AS a
) x 
ORDER BY divnumber DESC

Open in new window

0
Comment
Question by:m2ew
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
2 Comments
 
LVL 15

Accepted Solution

by:
pateljitu earned 500 total points
ID: 34954790
Group by clause on filename will do the job.

But in this case there is 'rating' is your select statement, if ratings varies you would still get each rows with different 'rating' and same filename. If 'rating' is not required removing from select statement will work.
select x.filename, (SELECT ratingsum / filenamecount) as divnumber
from (
SELECT  filename, rating,
                          (SELECT     SUM(rating) AS Expr1
                            FROM        mytable AS GV
                            WHERE      GV.filename = a.filename) AS ratingsum,
                          (SELECT     COUNT(*) AS Expr2
                            FROM          mytable AS GV
                            WHERE       GV.filename = a.filename) AS filenamecount
                          
FROM         mytable AS a
) x 
group by filename
ORDER BY divnumber DESC

Open in new window

0
 
LVL 41

Expert Comment

by:Sharath
ID: 34955912
You can simply do like this.
select filename,sum(rating)*1.0/ count(*) divnumber
  from mytable 
 group by filename
 order by divnumber desc

Open in new window

In fact, you can use avg function.
select filename,avg(rating) divnumber
  from mytable 
 group by filename
 order by divnumber desc

Open in new window

0

Featured Post

The Ultimate Checklist to Optimize Your Website

Websites are getting bigger and complicated by the day. Video, images, custom fonts are all great for showcasing your product/service. But the price to pay in terms of reduced page load times and ultimately, decreased sales, can lead to some difficult decisions about what to cut.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Dramatic changes are revolutionizing how we build and use technology. Every company is automating, digitizing, and modernizing operations. We need a better, more connected way to work together as teams so we can harness the insights from our system…
Your data is at risk. Probably more today that at any other time in history. There are simply more people with more access to the Web with bad intentions.
The viewer will learn how to look for a specific file type in a local or remote server directory using PHP.
Polish reports in Access so they look terrific. Take yourself to another level. Equations, Back Color, Alternate Back Color. Write easy VBA Code. Tighten space to use less pages. Launch report from a menu, considering criteria only when it is filled…

729 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question