Marketing or innovation? Chicken or egg?

Not so much "which came first?" as "which depends more on the other?" The answer, of course, is "yes."

To give Microsoft and other such companies...

Given a table Courses, with columns CourseID ('CIS101', etc) and Description and a table Classes, with columns ClassID (111, 112, etc), CourseID (FK to Courses table) and BeginDate, this will...

In rereading the original post, I have some questions. You mentioned that all the data would be

I got the impression that this...

Why?

That's the question I would like to ask the guy who, um, designed this and also the guy who accepted it. The first one has to be the second...

delete @Table

from @Table t

left join (

select Max(EmpID) as MaxID, Category

from @Table

...

Simple errors like this can be eliminated by the widespread use of aliases.

UPDATE c

SET c.RxPrescriberLName = p.LastName

FROM dbo.tblClmsRx c

INNER JOIN dbo.tblPharmacyClaimTemp...

If I am evaluating the soundness of a general rule, it doesn't bother me one bit that the rule would not be applicable to a 14 billion row MegaTable. At...

In a very bit database... 😉

However, such databases do exist and, truly, a numeric key would generally be...

I don't who RonKyle is arguing with, but it is not me. I never proposed using SSN (or any country's equivalent) as a Primary Key. In fact, I first mentioned...

Matt Miller (4/29/2008)

The primary characteristic for a primary key (in addition to uniqueness) is immutability, specifically because of its "deisgnated use" in table relations. And that's where I think...

GSquared (4/29/2008)

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The only reason I mention SSN as a problem is because SO many people think "oh, that's perfect!", and use it as a primary or unique key, and then...

The problem with any candidate key is that someone can come in afterwards and "what if" it to death. You can take any attribute and keep expanding the context to...

There is a little twist using nested transactions that can catch you. When you commit a transaction, you commit only the current level. When you rollback a transaction, you roll...

A key is any attribute (column) or combination of attributes which uniquely identify the tuple (row). That is, there should not be more than one row with the same value(s)...

Ah, I get it. So you can get a NULL value if your string is NULL or an empty string. Cool.:cool:

I think I remember NULLIF from years ago. I could...