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
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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!

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Developer IT

Retrieve names by ratio of their occurance - Developer IT

Retrieve names by ratio of their occurance

sql

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