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Let's assume you have the permissions required to make adds or changes.You must keep in mind that some databases are designed with constraints and triggers in place that may prevent you from inserting or updating anything.In general, only database administrators (DBAs) should manually insert records or make changes to existing records in a production database.
The same Discontinue Products method as above could be rewritten as: While this isn’t exactly what we would write if we were doing this by hand, it is far better than what Entity Framework would do on its own. The number of chunks depends on the size (number of fields and data size) of the records you are inserting. from Y” statement, to insert records into one table based on a Select from another set of tables.Net to open a database connection, create a command object, execute a SQL statement, iterate through the results and create your C# class instances (objects) manually. The following method marks a single product as discontinued, based on the product ID: As you can see, I’m using a simple LINQ query to get a single product with a Product ID matching the product ID parameter of the method, setting the Discontinued flag, and saving the changes. Let’s say I wanted to discontinue all products which are out of stock and have no units on order, instead of just one.The overhead of this is a little bit more than if I were using ADO. In this case, I have to execute one database call to retrieve the product, and one database call to update the data. Using only the built-in Entity Framework functionality, I would have to do something like this: This LOOKS pretty simple – I’m iterating through the context. Behind the scenes, Entity Framework is executing one SQL ‘select’ call to retrieve all the products, but when you call Save Changes, it is executing one SQL ‘update’ call per product.My other SQL lessons dealt exclusively with viewing data.The ability to query a table provides the help desk pro with a powerful troubleshooting tool.