Retrieve names by ratio of their occurance

Posted by jjiffer on Stack Overflow See other posts from Stack Overflow or by jjiffer
Published on 2010-06-15T18:08:27Z Indexed on 2010/06/15 18:12 UTC
Read the original article Hit count: 275

Filed under:

sql

Hello,

I'm somewhat new to SQL queries, and I'm struggling with this particular problem. Let's say I have query that returns the following 3 records (kept to one column for simplicity):
Tom
Jack
Tom

And I want to have those results grouped by the name and also include the fraction (ratio) of the occurrence of that name out of the total records returned.

So, the desired result would be (as two columns):
Tom | 2/3
Jack | 1/3

How would I go about it? Determining the numerator is pretty easy (I can just use COUNT() and GROUP BY name), but I'm having trouble translating that into a ratio out of the total rows returned.

Any help is much appreciated!

Related posts about sql

SQL SERVER – Concat Strings in SQL Server using T-SQL – SQL in Sixty Seconds #035 – Video

as seen on SQL Authority - Search for 'SQL Authority'
Concatenating string is one of the most common tasks in SQL Server and every developer has to come across it. We have to concat the string when we have to see the display full name of the person by first name and last name. In this video we will see various methods to concatenate the strings. SQL… >>> More
SQL SERVER – Concat Function in SQL Server – SQL Concatenation

as seen on SQL Authority - Search for 'SQL Authority'
Earlier this week, I was delivering Advanced BI training on the subject of “SQL Server 2008 R2″. I had great time delivering the session. During the session, we talked about SQL Server 2010 Denali. Suddenly one of the attendees suggested his displeasure for the product. He said, even though… >>> More
Error with SQL Server Setup 2012 on Windows 2012

as seen on Server Fault - Search for 'Server Fault'
I am trying to install SQL Server on Windows 2012. I was able to finally get the wizard up and running after making some changes on the server, but now it fails no matter what I do with the following error: TITLE: SQL Server Setup failure. SQL Server Setup has encountered the following error: … >>> More
How can I detect which version of SQL (eg SQL 2008 or SQL Azure)

as seen on Stack Overflow - Search for 'Stack Overflow'
I need to detect which version of SQL I am dealing with to perorm various tasks, I need specifically detect if I am on SQL 2008 or SQL Azure. How can I do this with detection code written in SQL? >>> More
Nested SQL Select statement fails on SQL Server 2000, ok on SQL Server 2005

as seen on Stack Overflow - Search for 'Stack Overflow'
Here is the query: INSERT INTO @TempTable SELECT UserID, Name, Address1 = (SELECT TOP 1 [Address] FROM (SELECT TOP 1 [Address] FROM [UserAddress] ua INNER JOIN UserAddressOrder uo ON ua.UserID = uo.UserID WHERE ua.UserID = u.UserID ORDER BY uo.AddressOrder ASC) q ORDER BY AddressOrder… >>> More

Developer IT

Retrieve names by ratio of their occurance - Developer IT

Retrieve names by ratio of their occurance

sql

Related posts about sql

SQL SERVER – Concat Strings in SQL Server using T-SQL – SQL in Sixty Seconds #035 – Video

SQL SERVER – Concat Function in SQL Server – SQL Concatenation

Error with SQL Server Setup 2012 on Windows 2012

How can I detect which version of SQL (eg SQL 2008 or SQL Azure)

Nested SQL Select statement fails on SQL Server 2000, ok on SQL Server 2005

Categories cloud