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With EF LINQ you retrieve the corresponding object, remove it from its collection, and then call Save Changes.
All together, that means you've made The multiple retrieval issue is one problem. If you wanted to set the credit limit to ,000 for all Customer rows where the Cust Credit Status column was set to "Premium," you'd use this SQL statement: Again, with ADO.
NET, you just issue that statement to the database server and assume that the server will optimize the heck out of it.
If you let EF LINQ mange the process, on the other hand, you'll first have to retrieve all the Premium Customer rows and then iterate through all of the resulting objects, updating each one individually.
As your Where clause becomes more complicated, though, you might want to check that integer result to see if it's non-zero -- a zero result would mean that you didn't find anything to delete.
Returning an integer result instead of a collection of objects also means that the Delete method will probably be the last method called in your LINQ statement. E Update method from a LINQ Where method that specifies the items to be updated (as with the EF. The difference with the Update method is that you must pass the method an object from the collection you're searching.You also can't pass the Update method a lambda expression of more than one line or pass a reference to another method in your application.Putting this all together, it means you must know what properties you're going to set .You'll still only make one trip to the database on the call to Save Changes because Entity Framework will bundle up all of the Update statements into a single transmission wrapped inside a transaction.However, each of those potentially unlimited number of Update statements will be executed individually because there's no way for the database engine to optimize these updates.