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The way the architecture works with the Data Adapter is that you can make any changes you want to the filled Data Set, and it won't affect the database until you call the Update method.When Update is called, the Data Adapter will attempt to execute each query (UPDATE, INSERT, DELETE) on every row of the Data Set that has been updated, inserted, and deleted.As you can see from listing 5-48, I created a filled Data Set and created a new Data Row using the Data Table. After creating a Data Row, I set its column values and called the Data Adapter's Update method and displayed data in the Data Grid.I added new rows to the Customers table with Customer Id, Customer Name, and Company Name (named Tst ID, Lana Jackob, and Mindcracker Inc., respectively). Adding data using a Data Adapter's Update method Listing 5-49 shows an example that edits row data.So, to insert data into a database, either a Connection and Command must be used, or a Data Adapter, which contains a Connection and a set of Commands must be used.In any case, the data is not literally updated as a batch, but in a looping construct that inserts the records one at a time.How you wish to do the insertion work is up to you.
After that I called the Data Adapter's Update method to save the changes to the database table. When a Data Table is populated from a database, it must be populated by a Data Reader, either as a member of a Data Adapter, or independently.The Data Reader or Data Adapter has the Connection to the database.As you saw in the Data Table, Data Row, and Data Column sections at the beginning of this article, you can use the Delete method of a Data Row to delete a row.The Add New method of the Data Table adds a row to a Data Table.The Find method returns the row with Customer Id = Tst ID.After that I assign values of the row and call the Data Adapter's Update method. Updating data using the Data Adapter's Update method sender, System. Listing 5-50 deletes the row with the value Tst ID.To change an existing row's data, you can directly assign a row's value.To save data to the data source, you need to call the Data Adapter's Update method. In VB6, using ADO I can loop thru the recordset,set the values of col A and call the Update method. For every record in tbl A where col B = 'abc', I want to update the value in col A.