update multiple table with transaction between try catch in sql server

I need to create script for entire database changes every week for my client to run on production server, when I was creating the script I need to check whatever I have created so I try to use transaction and to roll back every change, so I used try catch but it inserted many records in some master tables while there was some error in script and still error was not catching by try catch where i have written rollback transaction.

In this article we will see different ways what we can try and what is the best way to achieve our target.

Let's say we added some new columns to different tables and added some new values in our master table so first and some procedure changes, let's see what we think first

Begin Transaction
Begin Try    
   ALTER TABLE TableX ADD column1  varchar(50)
   ALTER TABLE TableY ADD column2  char(2)

   INSERT some_master (col1, col2, active) 
   VALUES (N'aaaaa', N'bbbbbb', 1)

   INSERT [dbo].[Lookup_Analyst] (col1, col2, active) 
   VALUES (N'xxxxxx', N'yyyyy', 1)


   -- Rollback    
   Rollback Transaction
End Try
Begin Catch
   Rollback Transaction
End Catch

Suppose last insert statement creates some error, say referential constraints or length of the column or any other issue, what will happen, It looks it will catch by try catch block and whatever changes we made in table structure and other insert statement will be rolled back, right?

No, table structure will be changes as well as other inserted records will not be rolled back

According to Microsoft:

There are two types of errors that will not be handled by TRY…CATCH if the error occurs in the same execution level as the TRY…CATCH construct:

• Compile errors, such as syntax errors that prevent a batch from executing.
• Errors that occur during statement-level recompilation, such as object name resolution errors that happen after compilation due to deferred name resolution.

So it is clear, we cannot use try catch to test our script as we discussed in the beginning of this article, so how we can test our script, we will use SET XACT_ABORT ON to catch the error and rollback

Here is the complete code to test our script

SET XACT_ABORT ON
BEGIN TRANSACTION    
   ALTER TABLE TableX ADD column1  varchar(50)
   ALTER TABLE TableY ADD column2  char(2)

   INSERT some_master (col1, col2, active) 
   VALUES (N'aaaaa', N'bbbbbb', 1)

   INSERT [dbo].[Lookup_Analyst] (col1, col2, active) 
   VALUES (N'xxxxxx', N'yyyyy', 1)


   -- Rollback    
   Rollback Transaction

It will give error if there would be any and other changes will be rolled back

Suppose we tested and and now we want to commit the records then we can change our rollback to commit, that's it.

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