SQL Server: Tips and Tricks
If you have a column in a SQL Server table that does not allow NULL values and you need to change it to allow NULLs, here is how you do it.
SQL Server is, by default, case insensitive; however, it is possible to create a case-sensitive SQL Server database and even to make specific table columns case sensitive. The way to determine if a database or database object is to check its "COLLATION" property and look for "CI" or "CS" in the result.
