You will hit this error Cannot assign a default value to a local variable in case you are running SQL 2005/below,and you try to declare a variable and assign it a value in one statement.
Something like -
DECLARE @Var Varchar(15) = 'Test'
Msg 139, Level 15, State 1, Line 0
Cannot assign a default value to a local variable
Variable declaration has been enhanced in SQL2008/above and I realized this today when I was deploying a code for multiple systems.
The same declaration mentioned above will work great for 2008/above
Apparently we also have the flexibility to just use one Declare statement to declare multiple variables -
DECLARE @Var Varchar(15) = 'Test', @Char Varchar(10) = 'Test2', @Char2 Varchar(10) = 'Test3'
These are indeed “feel good to have” enhancements !
[Update Added on 10/24/202]
In SQL2005 or below you will need to declare the variable and then assign it a value using Set statement.
DECLARE @Var Varchar(15) SET @Var = 'Test'
Thanks for reading.