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Updating data sources with data adapter

Note: If you are using SQL Server stored procedures to edit or delete data using a Data Adapter, make sure that you do not use SET NOCOUNT ON in the stored procedure definition. Table Mappings properties to facilitate the loading and updating of data. Update Command are generic templates that are automatically filled with individual values from every modified row through the parameters mechanism.

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Missing Schema Action property is set to Missing Schema Action. You may also have the Sql Data Adapter create the schema of the Data Set, including primary key information, before filling it with data using Fill Schema.In Lesson 3, we discussed a fully connected mode of operation for interacting with a data source by using the Sql Command object.In Lesson 4, we learned about how to read data quickly an let go of the connection with the Sql Data Reader.There are several parts involved in allowing this method to work: has been created, it is necessary to generate the additional statements required for inserting, updating and deleting data. There are several ways to do this, but in this tutorial you will see how this can most easily be done with database is read into a Data Grid View control. In this event, a DBConcurrency Exception will be thrown. For a list of these values, see the Sql Data Adapter constructor. Update(Data Set), a parameter should be added to the Insert Command, Update Command, or Delete Command. Source Column property of the Db Parameter object should be set to the name of the column.

This causes the rows affected count returned to be zero, which the Data Adapter interprets as a concurrency conflict. When an instance of Sql Data Adapter is created, the read/write properties are set to initial values. For every column that you propagate to the data source on Db Data Adapter.

, the connection to the database was continually maintained, unless explicitly closed.

It is also possible to work in a manner where a connection is only established when needed.

These are the mechanics of working with disconnected data.

Because the applications holds on to connections only when necessary, the application becomes more scalable.

This decouples the working data set from the database.