Handy SQL join explanation

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NickFitz replied

29 April 2010, 15:30
Originally posted by Spacecadet View Post

http://assets.en.oreilly.com/1/event...esentation.pdf

I was referring to standard SQL, not SQL with a bunch of proprietary extensions.
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Spacecadet replied

29 April 2010, 06:48
Originally posted by NickFitz View Post

Of course XSLT is Turing-complete, which SQL isn't

http://assets.en.oreilly.com/1/event...esentation.pdf
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NickFitz replied

29 April 2010, 04:51
Set theory is also crucial to understanding XSLT (the clue is in the constant references to "node sets" in the specs) yet hardly anybody using the language seems to understand that... then again, they don't understand the implications of it being a declarative language (as is SQL) either.

Of course XSLT is Turing-complete, which SQL isn't, so that probably confuses them as they develop complex ways to do stuff that would be simple if they knew what to do with sets.

Last edited by NickFitz; 29 April 2010, 04:54.
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Zippy replied

27 April 2010, 22:10
Originally posted by Spacecadet View Post

Maybe (just maybe) basic set theory should be explained before they are let anywhere near a database.

We did that at school and I still draw Venn diagrams sometimes
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Spacecadet replied

27 April 2010, 22:07
Originally posted by Moscow Mule View Post

I know this won't be of much use to you hardened SQL warriors out there, but I just found this link which I found very helpful in explaining joins to one of our developers.

Coding Horror: A Visual Explanation of SQL Joins

Maybe (just maybe) basic set theory should be explained before they are let anywhere near a database.
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suityou01 replied

27 April 2010, 11:11
Originally posted by Moscow Mule View Post

I know this won't be of much use to you hardened SQL warriors out there, but I just found this link which I found very helpful in explaining joins to one of our developers.

Coding Horror: A Visual Explanation of SQL Joins

Since SQL joins appear to be set-based

Good article though
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Cliphead replied

27 April 2010, 10:38
Originally posted by Moscow Mule View Post

I know this won't be of much use to you hardened SQL warriors out there, but I just found this link which I found very helpful in explaining joins to one of our developers.

Coding Horror: A Visual Explanation of SQL Joins

That's useful. I'm currently trying to get my head around SQL so I can create ad hoc reports.
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Moscow Mule started a topic Handy SQL join explanation

27 April 2010, 10:23
Handy SQL join explanation

I know this won't be of much use to you hardened SQL warriors out there, but I just found this link which I found very helpful in explaining joins to one of our developers.

Coding Horror: A Visual Explanation of SQL Joins
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