[AccessD] An interesting "feature" in SQL Server

Stuart McLachlan stuart at lexacorp.com.pg
Thu May 21 17:40:52 CDT 2009


Here, Here!

The yes/No field in Access is very badly designed.  

No field type sould be non-Nullable in any well designed DBMS.

You can define a Yes/No field as Not Required and/or give it a Default Value of Null, but it 
can still only hold 0 or -1 

You are far better off storing Yes/NO values as a Nullable Byte/Integer/Long and using a tri-
State checkbox on it

(Incidentally, how do they store -1 in a single bit? and why does changing a Yes/NO to a 
Byte convert a Yes values to 255? <g>)

-- 
Stuart

On 21 May 2009 at 17:15, Arthur Fuller wrote:

> That's a good approach, David. The rest of this thread really causes skin
> rash due to its misunderstanding of the purpose of NULL values. NULL is a
> valid value. I've said this before and I'm saying it again. Force a NULL
> value to anything else (which includes defaulting a column to some value) is
> IMO a fundamental design error, indicative of one of two problems:
> 
> 1. you don't understand the data domain
> 2. the domain itself is incoherent.
> 
> My $.02.
> Arthur
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