SQL Server set ansi_null_default off

Question

Hi All
Can someone tell me the difference between having the ANSI_NULL_DEFAULT [ON/OFF]
Ive written code below and the both create nullable columns so im very confused?
thanks
alter database CloseMonitoring
set ansi_null_default off
create table tbl_compare_off
[id] int
alter database CloseMonitoring
set ansi_null_default on
create table tbl_compare_on
[id] int

Answer 1

This is what MSDN says
When SET ANSI_NULLS is ON, a SELECT statement that uses WHERE column_name = NULL returns zero rows even if there are null values in column_name.
A SELECT statement that uses WHERE column_name <> NULL returns zero rows even if there are nonnull values in column_name.
When SET ANSI_NULLS is OFF, the Equals (=) and Not Equal To (<>) comparison operators do not follow the ISO standard. A SELECT statement that uses WHEREcolumn_name = NULL returns
the rows that have null values in column_name. A SELECT statement that uses WHERE column_name <> NULL returns
the rows that have nonnull values in the column. Also, a SELECT statement that uses WHERE column_name <> XYZ_value returns all rows that are not XYZ_value and
that are not NULL.
http://technet.microsoft.com/en-us/library/ms188048.aspx
Also SET ANSI_NULL OFF is a deprecated feature. 
 Important
In a future version of SQL Server, ANSI_NULLS will always be ON and any applications that explicitly set the option to OFF will generate an error. Avoid using this feature in new development work,
and plan to modify applications that currently use this feature.
Satheesh
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