Updating datasource using dataadapter
Close() But if the Sql Data Adapter object is used to insert/update/delete records in the data source, is it ALWAYS necessary to first make the necessary changes in the Data Set for the data source to reflect the changes? The code I have shown in my first post (which doesn't use Sql Data Adapter) inserts a row in the data source....correct? If you want to update your Data Source without that line you have commnted then try to fill again your Data Set with the Updated values from the Data Base...Select Command = sql Cmd d Set = New Data Set sql Dapter. If the question is: Why is it needed to specify the values twice (when the new Data Row is created and also when the parameters are defined): First, while adding a new Data Row: d Row(1) = "" Then the answer is "No, you don't need to indicate this twice".
Open(); Sql Data Adapter da = new Sql Data Adapter(sql Select, conn); Data Set ds = new Data Set(); // define update logic for the data adapter // load data from the data source into the Data Set da. Hi Your article is very good.i am new to database.i want to ask a question that in update your are changing the values but how can we Subtract the values in example a stock column contain 20,we give input as 5,then how can we subtract 5 from stock column and then stock column updated to 15.In Lesson 3, we discussed a fully connected mode of operation for interacting with a data source by using the Sql Command object. NET, a Data Adapter functions as a bridge between a data source, and a disconnected data class, such as a Data Set.At the simplest level it will specify SQL commands that provide elementary CRUD functionality. create the connection and data adapter as with custom update logic // use a command builder to define updating logic Sql Command Builder cb = new Sql Command Builder(da); // generate updating logic for command objects cb. Fill(ds, "Orders"); // start the transaction Sql Transaction tran = conn.
modify the data in the Data Set // submit changes, commit or rollback, and close the connection try catch (Exception) finally // ... Get Update Command(); // load data from the data source into the Data Set da.
Fill(ds, "Orders"); // start the transaction Sql Transaction tran = conn.
Begin Transaction(); // associate transaction with the data adapter command objects da.
Data Adapter provides the data source connection and the ability to perform disconnected operations.
Data Adapter opens connections only when necessary and closes them immediately after completing a task; for example, when populating a Data Set, it opens the connection, retrieves data to put into the Data Set, and then closes the connection.
For example, the Sql Data Adapter performs the following tasks when filling a Data Set with data: In between the Fill and Update operations, data source connections are closed and you are free to read and write data with the Data Set as you need.