Guru's Guide to SQL Server Architecture and Internals, The

Optimizing Transactional Code

There are a number of general guidelines for writing efficient transaction-oriented T-SQL. Here are a few of them.

• Keep transactions as short as possible. Once you've determined what data modifications need to be made, initiate your transaction, perform those modifications, and then end the transaction as soon as possible. Try not to initiate transactions prematurely.

• Limit transactions to data modification statements when practical. Don't initiate a transaction while scanning data if you can avoid it. Though transactions certainly impact reading data as well as writing it (e.g., dirty and nonrepeatable reads, phantom rows, and so on), it's often possible to limit them to just those statements that modify data, especially ...