Context submitchanges is not updating the database
If we inserted a new person then this also wouldn’t stop our application from working, unless the new column was set to be NOT NULL, however we wouldn’t be able to fill in that information.
Changing column data types Changing the types in our database could cause our application to stop functioning.
If the data structure is changed without your application being updated or knowing about the change then you will run into problems.
In this application, I will be working with the following entity. For example, if we wanted to write everything out to the console we could do this: Adding additional columns If we added an additional column, say email, onto our table then the above could would still work fine however we would never be able to access that additional column until we regenerated our Data Context (see below).
Regenerating our Data Context So, if you are changing the underlying table, updating the Data Context in your system is also required.
In Visual Studio 2008 there are only two ways to update a Data Context.
If our query was like below, then it wouldn’t cause an exception as Phone would never be called.
However, when inserting data we will always get a Sql Exception even if the column was not populated as Linq will try and insert null into the column.
Changes to the underlying database structure is a problem with any application and data access, be it and Datasets, Sub Sonic, Linq or any other approach.
You’d like to delete the old row and then insert the new data rather than an Update, because of some triggers which run some complex business logic.
Unfortunately, a sequence of an Insert followed by a Delete does not execute on SQL Server like you would expect.
This is done by enclosing the operations in a block: Note: To use Transaction Scope, you need to reference System. If you are using SQL Profiler to watch the SQL being executed, note that you will always see the Update and Insert statements irrespective of whether the Transaction was rolled back or not, because SQL Profiler does not indicate Transactions, but let that not confuse you.
The data will not be affected in case of a Rollback.
And all in all, it's a pretty straightforward 10 lines of code.