Thanks for once again dropping some inside knowledge on us Keith   For those of us who get a headache from 3-valued logic, just try...

On a not so philosophical nature; if you want to search for unknow values you should consider using "NOT IN" in your WHERE clause or a <> join.

Both of which,...

You're right, an invalid key throws an exception in the code.  Because it's running in the same process space, it requires a server re-start.  I left out extra exception handling...

Hi Tom, thanks for the comments.

The main method I can think of for testing of UNKNOWNs is to perform three comparisons in SQL-92:

IF x = y THEN   -- perform if...

NULL is not a value, it is a special mark (or flag) indicating the absence of a value.  Not sure about the second part of your question - in many...

These are symmetric encryption algorithms, so you have to use the same key to decrypt that you used to encrypt.

You might not like the guy, but you gotta admit that he's always good for a confusing quote I was going to...

Excellent points and thanks for the direct link to Pascal's paper.

As was mentioned before though, even if you properly normalize your data by placing data that might be deemed "inapplicable"...

Thanks for the comments Keith. It's good to have feedback from the folks who set the standards. I cited the SQL-92 standard specifically because the majority of ANSI-compliance...

There's a lengthy discussion above about this particular issue above - without rehashing too much, there are dozens of schemes to try to overcome this particular SQL limitation. Some...

Hi Jesper,

Thanks for the comments. That's an excellent point about the two columns not being equal despite both being NULL, and SET ANSI_NULLS being OFF. Also, appreciate the...

Thanks for the comments. The adequacy of NULLs has been a hotly debated topic since the beginning, even among the most seasoned veteran SQL Academics and DBAs, including the...

Yes, you mentioned that it's not a real Transact-SQL statement. I was expanding on what you said it "isn't" by explaining what it actually "is".

As JT noted above,...

You really should state up top - in BIG BOLD LETTERS - that this is just an advertisement for your company's product.

"GO" is not a real SQL statement. It's a batch termination indicator for Query Analyzer. You might want to point out that trying to use "GO" in...