Rowupdating in gridview not working
Therefore, in situations where pessimistic concurrency is used, there's typically a timeout that, if reached, cancels the lock.
Ticket sales websites, which lock a particular seating location for short period while the user completes the order process, is an example of pessimistic concurrency control.
Let's use the exact same SQL query used for the SELECT Product ID, Product Name, Supplier ID, Category ID, Quantity Per Unit, Unit Price, Units In Stock, Units On Order, Reorder Level, Discontinued, (SELECT Category Name FROM Categories WHERE Categories. Category ID) as Category Name, (SELECT Company Name FROM Suppliers WHERE Suppliers. Supplier ID) as Supplier Name FROM Products Table Adapter in the Original DAL (Click to view full-size image) Before moving onto the next screen, click the Advanced Options button. Products Optimistic Concurrency Data Table = _ Adapter.
Figure 3: Connect to the Same Northwind Database (Click to view full-size image) Next, we are prompted as to how to query the data: through an ad-hoc SQL statement, a new stored procedure, or an existing stored procedure.
For a web application that allows multiple users to edit data, there is the risk that two users may be editing the same data at the same time.
In this tutorial we'll implement optimistic concurrency control to handle this risk.
Figure 1 graphically depicts this series of events.
Figure 1: When Two Users Simultaneously Update a Record There s Potential for One User 's Changes to Overwrite the Other 's (Click to view full-size image) Similarly, when two users are visiting a page, one user might be in the midst of updating a record when it is deleted by another user.