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Which data type is preferable over identity column?

An Identity column in SQL-SERVER It is automatically inserted the value in identity column whenever new record gets inserted into the table.

--Create Student

if object_id('Student') is null
create table Student(id tinyint identity(1,1) ,Name varchar(20),Marks int)

If we observe above Create table statement the Id column is identity column and its data type is tinyint.

We know that tinyint accepts 0 to 255 numbers range.

--insert data into Student table.
Declare @start int=1
while (@start<=256)
begin
                insert into Student(Name,Marks) values('Rakesh',500)
set @start=@start+1
end

In the above while loop we are trying to insert same record in 256 time. The identity column automatically supplied value. The 1-255 records gets inserted successfully.256 record get an error because of tinyint accepts 0-255 records only.
(1 row(s) affected)

(1 row(s) affected)
Msg 8115, Level 16, State 1, Line 4
Arithmetic overflow error converting IDENTITY to data type tinyint.
Arithmetic overflow occurred.

The Last row got error.

Note: Preferred data type is over identity column is based on requirement. If it daily increments take large data type just likes int, bigint...  






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