How to loop through a dataset using t-sql

Posted on 2009-03-30
Last Modified: 2012-05-06
I have a database that has different prices for different items from different stores.  I've given each item a standard number, and an indicator to tell where the item came from.  What I'd like to do is create a procedure to give me a percent price difference based on the average of all items.  So for the sample data below, I want the average price of all items from Wal-Mart, the average price of all items from Shaw's and the average price of all items from Meijer.  Then I want the percent difference between all three.  So if the avg for Wal-Mart is 2.82, and Shaw's is 2.76, then the pct diff between Shaw's and Walmart is 2.13%

The other thing is the data is grouped by department.  So I have line items for dairy, bread, paper products, etc.  The same calcuation would have to be done for all of the departments.

Thanks for help on this.

Ven_Ind  Vendor     Item                                        Price       Dept_Ind
1             Wal-Mart	Eggs, large, dozen	                3.13       12
1             Wal-Mart	Eggs, medium, dozen	3.05       12
1             Wal-Mart	Cheese, sliced, American	2.89       12
1             Wal-Mart	Cheese, sliced, Swiss	2.74       12
1             Wal-Mart	Sour cream	                2.59       12
1             Wal-Mart	Sour cream,light	                2.52       12
2             Shaw's	Eggs, large, dozen	                3.13       12
2             Shaw's	Eggs, medium, dozen	2.97       12
2             Shaw's	Cheese, sliced, American	2.82       12
2             Shaw's	Cheese, sliced, Swiss	2.67       12
2             Shaw's	Sour cream	                2.52       12
2             Shaw's	Sour cream,light	                2.45       12
3             Meijer	Eggs, large, dozen	                2.45       12
3             Meijer	Eggs, medium, dozen	3.20       12
3             Meijer	Cheese, sliced, American	3.13       12
3             Meijer	Cheese, sliced, Swiss	3.05       12
3             Meijer	Sour cream	                2.97       12
3             Meijer	Sour cream,light	                2.88       12

Open in new window

Question by:kenyayvette
LVL 41

Accepted Solution

ralmada earned 500 total points
ID: 24022580
Please try this:
select a.vendorid, a.vendor, a.avgprice, b.vendorid, b.vendor, b.avgprice, ((a.avgprice - b.avgprice) / a.avgprice) as ptcdifference from (
select vendorid, vendor, avg(price) as avgprice from yourtable
group by Vendor) a
cross join (select vendorid, vendor, avg(price) as avgprice from yourtable
group by Vendor) b
where a.vendor < b.vendorid

Open in new window


Author Comment

ID: 24024086
Thank you so very much, that is exactly what I needed.

Featured Post

PRTG Network Monitor: Intuitive Network Monitoring

Network Monitoring is essential to ensure that computer systems and network devices are running. Use PRTG to monitor LANs, servers, websites, applications and devices, bandwidth, virtual environments, remote systems, IoT, and many more. PRTG is easy to set up & use.

Question has a verified solution.

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

Suggested Solutions

When writing XML code a very difficult part is when we like to remove all the elements or attributes from the XML that have no data. I would like to share a set of recursive MSSQL stored procedures that I have made to remove those elements from …
So every once in a while at work I am asked to export data from one table and insert it into another on a different server.  I hate doing this.  There's so many different tables and data types.  Some column data needs quoted and some doesn't.  What …
Microsoft Active Directory, the widely used IT infrastructure, is known for its high risk of credential theft. The best way to test your Active Directory’s vulnerabilities to pass-the-ticket, pass-the-hash, privilege escalation, and malware attacks …
Established in 1997, Technology Architects has become one of the most reputable technology solutions companies in the country. TA have been providing businesses with cost effective state-of-the-art solutions and unparalleled service that is designed…

856 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