Introduction
My friend has been working in a Software Company as a “Database Developer” for the last couple of years. When we met for some reason, most of the time I find out that he is very upset. Several times, I asked him why he was looking so upset, and every time he didn't reply to my question.
Background
One evening, he came to my home and told me that he didn't know why his boss was always getting angry when he altered the Microsoft SQL Server database objects such as storedProcedure, functions, views, etc.
Discussion
I just smiled and said, "Don’t worry, my friend, I will show you why."
In this section, I would link to show you why
DROP AND CREATE database objects is much better than the
alter objects. Let’s consider the scenario listed below:
(i) For example, we will create a simple storedProcedure name “
[dbo].[spGetEmployees]” first.
(ii) Get that storedProcedure information from the system table by executing “
sp_help”. Figure (a) shows the created time, after creating and performing
ALTER.
Figure (A)
(iii) Record the storedProcedure created time.
(iv) After few minutes, alter the storedProcedure and do the scenario (ii) again.
(v) Few minutes later, do some update to the storedProcedure and this time we do not use
ALTER, we use
DROP AND CREATE process. Finally, do the scenario (ii) again. Figure (b) shows the created time which is updated, after creating and performing
DROP AND CREATE.
Figure (B)
Result
Do you find anything that makes sense; I hope you got the point, after creating an SQL database object and you alter over and over again, the created time of that object remaining the same. Sometimes, we need to track database object modification information.
Conclusion
So I would always prefer “DROP AND CREATE” rather than the ALTER statement.
