Should Data types be sizes of powers of 2 in SQL Server?

Question

What are good sizes for data types in SQL Server? When defining columns, i see data types with sizes of 50 as one of the default sizes(eg: nvarchar(50), binary(50)). What is the significance of 50? I'm tempted to use sizes of powers of 2, is that better or just useless?

Update 1 Alright thanks for your input guys. I just wanted to know the best way of defining the size of a datatype for a column.

Answer 1

There is no reason to use powers of 2 for performance etc. Data length should be determined by the size stored data.

Answer 2

Why not the traditional powers of 2, minus 1 such as 255...

Seriously, the length should match what you need and is suitable for your data.

Nothing else: how the client uses it, aligns to 32 bit word boundary, powers of 2, birthdays, Scorpio rising in Uranus, roll of dice...