Question

I have a table with a column of type varbinary(max). I have some rows that have data in that column while others do not; they are null.

My question is: does the column with NULL also occupy 2 bytes per row? I am using SQL Server 2008 R2.

Thank you

Answer 1

This article http://aboutsqlserver.com/2010/08/11/how-sql-server-stores-data-extents-data-pages-data-row-for-in-row-data/ is what you need to read.

There is no data to store, but the metadata will occupy

• 1 bit in the NULL bitmap (each 8 nullable columns = 1 byte)
• 2 bytes in the variable offset array. Unless it is the last column or all columns prior are NULL columns