December 2011
Intermediate to advanced
336 pages
10h 10m
English
Anytime more than one user will be accessing an application or database simultaneously, the development task gets much more complex. Supporting multiple users (a requirement for most business applications) requires planning for multiuser conflicts that might occur when two users attempt to update the same data at approximately the same time. You can do this by locking records, but locking records can introduce other problems that your application needs to handle.
This objective covers planning for simultaneous access from multiple users, a concept known as concurrency. It also describes transactions that group together multiple operations so that all operations succeed or fail together. ...