Optimistic Concurrency Control:?

• Optimistic Concurrency assumes that conflicts will be rare and allows multiple

users to read and modify data without locking it.

• When updating data, you compare the current data in the database with the data the

user fetched earlier (usually by checking a timestamp or version number). If the data

has been changed by someone else, you throw a concurrency exception.

Steps:

• Add a timestamp or row version column to the table.
• When updating, check if the timestamp or row version has changed.

Example:

SqlCommand command = new SqlCommand("UPDATE Customers SET

CustomerName = @CustomerName WHERE CustomerID = @CustomerID AND

RowVersion = @RowVersion", connection);

command.Parameters.AddWithValue("@CustomerName", customerName);

command.Parameters.AddWithValue("@CustomerID", customerId);

command.Parameters.AddWithValue("@RowVersion", rowVersion);

Follow:

If the RowVersion has changed between the time the user fetched the data and the time

they attempt to update, the update will fail, and an exception will be thrown.