I found this in the FAQ section and found it hard to believe that the use of Nulls id descouraged? What are you to do? Fill a char field with space? Int with 0? And what about Date? 01/01/1900? These are all valid values. I took the 20 question quiz and it had a question on this as well, mostly in reference to access data. I Thought an Index on the column would work well, but the quiz said to make the column not null with a default value. Huh? Isn't there more overhead associated with that? Here is the FAQ, but does anyone else have any insight in to nulls? Doesn't Nulls, being attributive nonexistance, have a place? I always thought so. SQL Server Performance Questions & Answers Question Can the use of NULLS in a database affect performance? Answer Yes, SQL Server's performance can be affected by using NULLS in your database. There are several reasons for this. First, NULLS that appear in fixed length columns (CHAR) take up the entire size of the column. So if you have a column that is 25 characters wide, and a NULL is stored in it, then SQL Server must store 25 characters to represent the NULL value. This added space increases the size of your database, which in turn means that it takes more I/O overhead to find the data you are looking for. Of course, one way around this is to use variable length fields instead. When NULLs are added to a variable length column, space is not unnecessarily wasted as it is with fixed length columns. Second, use of the ISNULL clause in your WHERE clause means that an index cannot be used for the query, and a table scan will be performed. This can greatly reduce performance. Third, the use of NULLS can lead to convoluted Transact-SQL code, which can mean code that doesn't run efficiently or that is buggy. Ideally, NULLs should be avoided in your SQL Server databases.