Updating linq to sql entities
For files the database connection string is defined in the web.config file as: We can use a connection string from the web.config file or we can pass a connection string as a parameter in the constructor of the Data Context class to create an object of the Data Context class.
The SELECT Operation Conculsion To perform select, insert, update and delete operations we create a table and create a data context class; in other words a dbml file.
For more information about how to use the Object Relational Designer and SQLMetal tools to generate classes that are serializable by using Windows Communication Foundation (WCF), see How to: Make Entities Serializable. The only way for an entity to be detached from its original data context is for it to be serialized.If you try to attach an undetached entity to a new data context, and that entity still has deferred loaders from its previous data context, LINQ to SQL will thrown an exception.An entity with deferred loaders from two different data contexts could cause unwanted results when you perform insert, update, and delete operations on that entity. Product _ In products ' Persist to a List(Of Product) declared at class scope.In this file designer view we drag and drop the COURSE table from the Server Explorer.This data context class is an Object and table mapping and we perform the operation on the object and database updated according to the action using the submit Changes() method.