SQL in 24 Hours, Sams Teach Yourself, 7th Edition

Hour 11

Managing Database Transactions

What You’ll Learn in This Hour:

• ▶   The definition of a transaction

• ▶   The commands used to control transactions

• ▶   The syntax and examples of transaction commands

• ▶   When to use transactional commands

• ▶   The consequences of poor transactional control

So far, this book has discussed all-or-nothing scenarios for manipulating data inside a database. However, in more complicated processes, you need the capability to isolate changes so that they can be applied or rolled back to an original state at will. This is where transactions come in. Transactions give you the additional flexibility to isolate database changes into discrete batches and undo those changes if something goes wrong. In this hour, you ...