Handy SQL join explanation

[Moscow Mule]

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

 

[Cliphead]

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.

 

[suityou01]

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

 

[Spacecadet]

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.

 

[Zippy]

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

 

[NickFitz]

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.

 

[Spacecadet]

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

http://assets.en.oreilly.com/1/event/27/High Performance SQL with PostgreSQL Presentation.pdf

 

[NickFitz]

http://assets.en.oreilly.com/1/event/27/High Performance SQL with PostgreSQL Presentation.pdf

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