Quick Check

1.	How can you tell SQL Server to roll back a transaction in case an error occurs?
2.	What is the difference between the functions @@ERROR and ERROR_NUMBER()?
3.	Can you commit a transaction in the catch block?

Answers

1.	In the event of an error that might keep a transaction from completing successfully, you can tell SQL Server to roll back a transaction by setting the XACT_ABORT session option to ON.
2.	The function @@ERROR returns the error number of the previously executed statement and can be used outside of a catch block. The function ERROR_NUMBER() returns the error number that belongs to the error that caused control to be transferred to the current catch block. If not inside of a catch block, ERROR_NUMBER() returns NULL.
3.	Yes, you can commit a transaction in the catch block if the transaction is committable. Use the XACT_STATE() function to find out if it is.