Dynamic Select Sample (.NET)
From RemObjects Wiki
The sample shows how to use the DynamicSelect feature to decrease network traffic and server load, retrieving only needed columns.
Examine the code
- Take a look at the bFill_OnClick event handler to see how you can fill the DataSet using the DynamicSelect feature:
this.fLocalDataSet = lUseDynamicSelect? (DataSet)new WorkersDataset(): (DataSet)new WorkersFullDataset(); this.workersBindingSource.DataSource = this.fLocalDataSet; this.workersBindingSource.DataMember = "Workers"; this.dgvCustomers.DataSource = this.workersBindingSource; this.remoteDataAdapter.DynamicSelect = lUseDynamicSelect; ... this.remoteDataAdapter.Fill(this.fLocalDataSet);
- Look at the bUpdate_OnClick event handler to see how updates of the local DataSet can be applied to the SQL server database:
Note that the Update operation always uses the DynamicSelect mode of the previous Fill operation.
- Run the Sample Server.
- Run the Dynamic Select Sample.
- Try to fill and update the DataSet using the DynamicSelect feature.
- Look at the server log to see the SQL command used on the server and estimate the amount of data sent to the client application.
- Try to fill and update the DataSet not using the DynamicSelect feature.
- Look at the server log again to see the amount of data sent to the client application by the server.
Editions and Languages
- Data Abstract for .NET — available in C#, Embarcadero Prism and VB
- Data Abstract for Delphi — available here