Modifying the Data
Use the adapter's Update method to update the data. This overloaded method can take a DataTable as a parameter and will commit all the changes made to the data source. The name of the data table can be passed as an argument and can also be used to update the entire dataset in a more traditional manner. When using a data table as an argument to the Update method, the adapter evaluates the changes that have been made to the data table and executes the appropriate command for each row (INSERT, UPDATE, or DELETE).
The following example updates the Name of one of the [Hive].[Default].Customers entries.
C#
using (PrestoConnection connection = new PrestoConnection(connectionString)) { PrestoDataAdapter dataAdapter = new PrestoDataAdapter( "SELECT Id, Name FROM [Hive].[Default].Customers", connection); dataAdapter.UpdateCommand = new PrestoCommand( "UPDATE [Hive].[Default].Customers SET Name = @Name " + "WHERE Id = @Id", connection); dataAdapter.UpdateCommand.Parameters.Add(new PrestoParameter("@Name", "Name", DbType.String )); dataAdapter.UpdateCommand.Parameters.Add(new PrestoParameter("@Id", "Id", DbType.String )); dataAdapter.UpdateCommand.Parameters[1].SourceVersion = DataRowVersion.Original; DataTable table = new DataTable(); dataAdapter.Fill(table); DataRow firstrow = table.Rows[0]; firstrow["Name"] = "Jon Doe"; dataAdapter.Update(table); Console.WriteLine("Rows after update."); foreach (DataRow row in table.Rows) { Console.WriteLine("{0}: {1}", row["Id"], row["Name"]); } }
VB.NET
Using connection As New PrestoConnection(connectionString) Dim dataAdapter As New PrestoDataAdapter( "SELECT Id, Name FROM [Hive].[Default].Customers", connection) dataAdapter.UpdateCommand = New PrestoCommand( "UPDATE [Hive].[Default].Customers SET Name = @Name " + "WHERE Id = @Id", connection) dataAdapter.UpdateCommand.Parameters.Add(new PrestoParameter("@Name", "Name" DbType.String )) dataAdapter.UpdateCommand.Parameters.Add(new PrestoParameter("@Id", "Id", DbType.String)) dataAdapter.UpdateCommand.Parameters(1).SourceVersion = DataRowVersion.Original Dim table As New DataTable() dataAdapter.Fill(table) Dim firstrow As DataRow = table.Rows(0) firstrow("Name") = "Jon Doe" dataAdapter.Update(table) Console.WriteLine("Rows after update.") For Each row As DataRow In table.Rows Console.WriteLine("{0}: {1}", row("Id"), row("Name")) Next End Using
CData Method Extensions
If you want to retrieve the compound primary key after performing an INSERT, the best method to use depends on what type of INSERT was just executed.If the INSERT was a single update/delete statement, use the connection.GetLastResult() method to retrieve the inserted ID or IDs.
If the INSERT was a batch operation and only one row was updated, use connection.GetLastResult() to get the insertedID. This is the same as retrieving an ID from single update/delete.
If the INSERT was a batch operation and multiple rows were updated, query SYS_LASTRESULTINFO directly to retrieve the inserted IDs from the LASTRESULTINTO#TEMP table.