Tim Johnson <[EMAIL PROTECTED]> wrote on 02/23/2006 12:26:35 PM:

> Let's say I have a query that performs
> 
> "select * from Account"
> 
> one of the columns from "Account" (city) is actually a key which may
> be either numeric or character.
> 
> There is a table called "City" which contains keys and names of cities.
> 
> and I want the City.Name value where Account.city matches City.ID.
> 
> I need the most efficient way to do this: examples, keywords, and
> URLs to relevant documentation are all welcome.
> 
> thanks
> tim
> 
> -- 
> Tim Johnson <[EMAIL PROTECTED]>
>       http://www.alaska-internet-solutions.com
> 

First off, columns can either be numeric or character-based not both. You 
can store arrangements of the characters "0" through "9" in a 
character-based field but those are not numbers, they are strings that 
look like numbers.

Your description makes it sound like you have a table that has data in a 
column called 'city' that looks like:

Atlanta
Boston
15
10
24
Paris
Rome
215
Tokyo

or am I mistaken? 

Back to your direct question: How you "link" two tables is called 
"joining". There are tons of examples and tutorials of how to join tables. 
One of my favorites is

http://sqlzoo.net/

It takes you through everything you need in order to get your feet wet and 
it gives you the ability to immediately try out what you are being taught. 
If you work through their examples you should be able to make some decent 
headway.

I also recommend you read this article about normalization:
http://dev.mysql.com/tech-resources/articles/intro-to-normalization.html


There is a query that can do what you want but I strongly suggest you 
review your design before moving too much farther into this project.

Shawn Green
Database Administrator
Unimin Corporation - Spruce Pine

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