Kform Data Access (ADO .NET)

 In Kform Project Manager 2007 ADO .NET is used to implement the Data-access Layer for the connection with the SQL Server Database.  A data provider that wants to make its data available to .NET clients via ADO.NET implements a standard set of .NET objects that connect the data provider to interested clients. Microsoft has provided an implementation of these objects for SQL Server in its .Net Framework these classes are part of the .NET Common Language Runtime (CLR).   ADO.NET provides its actual data in the form of a disconnected DataSet object that represents a collection of data that results from one or more queries. It contains internal tables and provides methods that allow access to the tables’ rows and columns. It also contains a schema describing its internal structure.

Windows Forms contain controls that know how to take a Data Set object and render its contents for display. The purpose of using a Data set in KForm is to implement Data Caching. The request sent by the client for retrieving data from different tables will be acknowledged by sending all the tables and the schema in the dataset in one cycle. Now all other requests of retrieving data by the client will be fulfilled from the client side without going to the server again and again. In this approach we have the advantage of preventing inconsistent data and deadlocks at the database level because every client has its own database at the client side and no frequent DB access is in practice.

The data services in an application include the logic necessary to store, retrieve, and modify data, as well as the data integrity rules that the application must enforce. Data services provide the lowest visible level of detail used to manipulate data. For example, a data service may:

• • Maintain persistent application data.
• • Provide the ability to define, create, read, update, and delete.
• • Hide the design, implementation, and location of data.