Sams Teach Yourself ADO.NET in 24 Hours

Hour 14. Managing ADO.NET Concurrency

Concurrency is critical in any multiuser environment where data is to be updated. Concurrency, as you can see in Figure 14.1, is best thought of as “multiple users vying to update data without affecting each other as they update it.” In this illustration, each client application (Client A, Web Client B, and Web Client C) has read the same Customer data values at approximately the same time. They all see the same Customer data, and some will choose to update this data and expect their updates to be successful. The type of concurrency model you utilize will directly determine how these data resources are treated (held/locked/enqueued), what type of performance to expect, and how scalable your application will ...