Ok, I just started studying for the 70-432 exam (SQL2k8 implementation/maintenance.) I bought a book for it and one of the questions in the first chapter reads as follows:
You have a database table with a varchar(600) field in it. Most of the records in the table have a NULL value for this field. How can you save space?
A. Move the data into a second table.
Now, I would've expected the answer to be (B) but the book is telling me (A) is the answer.
Can anyone tell me why this is the case?
It appears B is the correct answer and they forgot to include the rationale excluding A.
Actually, A would increase the size required if anything due to redundant row overhead introduced in adding a second table.
If the Publisher has a section for adding errata you may want to point out that their answer is not clear.
The thing about answers that these instructional books mess up is they make you research the answers deeper :)
Not exactly the intended result but one that does expand your understanding.
answered Nov 11 '09 at 10:36 AM
This doesn't suprise me, the book is full of mistakes.
Check out the published corrections under this MSKB That's not a comprehensive list. My favorite was when the book discusses storage & refers to IDE hard drives in brackets as Integrated Development Environment.
answered Nov 11 '09 at 11:58 AM
That looks wrong to me. Maybe I'm just not thinking, but it strikes me that anything that would be solved by A would also be solved by an index rebuild. I am pretty sure the answer is B on that one.
answered Nov 10 '09 at 04:37 PM
Matt Whitfield ♦♦