POV-Ray : Newsgroups : povray.off-topic : Question for SQLers out there : Re: Question for SQLers out there Server Time
11 Oct 2024 03:17:12 EDT (-0400)
  Re: Question for SQLers out there  
From: Tom Austin
Date: 13 Feb 2008 08:59:25
Message: <47b2f7bd$1@news.povray.org>
Gail Shaw wrote:

> "Tom Austin" <taustin> wrote in message news:47b203ce$1@news.povray.org...
> 
>> My SQL statement is likely less efficient than using JOIN.
>> depending on the DB being used
> 
> On MS SQL Server, they will be identical.
> 
>> I've tried learning JOINS before, but it never stuck.
>> I guess I learned it all wrong int he first place.
>>
>> Does someone have some simple and clear examples on JOINS and where they
>> work?
> 
> Not offhand. I could probably write an explaination for you (tomorrow) that
> might be clear.
> What are you confused about?
> 

Actually you have already provided some good examples in your other posts.

So, what I am really picking up is:

My SQL statement is perfectly valid, but is not robust.  A 'join' might 
be left out which can cause a very costly query - tho on a small DB this 
might not matter except for causing a 'bug'.


Using JOIN provides for a more robust way of querying multiple tables. 
You are required to provide the match condition.


Using my example SQL method is perfectly valid, but requires more caution.



Thanks Gail, I really do appreciate your responses.


Tom


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