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Improving Performance While Filling a DataSet

[ Team LiB ] Recipe 9.9 Improving Performance While Filling a DataSet Problem Given a DataSet containing many related tables that takes a long time to fill | Team LiB Recipe 9.9 Improving Performance While Filling a DataSet Problem Given a DataSet containing many related tables that takes a long time to fill you need to improve the performance. Solution Use the EnforceConstraints property of the DataSet and the BeginLoadData and EndLoadData methods of the contained DataTable objects to improve performance while filling a complex DataSet. The sample code contains one event handler and one method Go Button.Click Times the filling of the DataSet created by the CreateDataSet method described next . The EnforceConstraints property of the DataSet is set as specified and the BeginLoadData and EndLoadData methods of the contained DataTable objects are used if specified. A DataAdapter is used to fill a specified DataSet with data from the Orders and Order Details tables in the Northwind database. Ten iterations are performed and the total fill time is returned in ticks which are 100-nanosecond intervals. CreateDataSet This method builds a DataSet containing the table schema for the Orders and Order Details tables from the Northwind database and creates a data relation between the tables. The DataSet is returned by the method. The C code is shown in Example 9-12. Example 9-12. File DataSetFillPerformanceForm.cs Namespaces variables and constants using System using System.Configuration using System.Windows.Forms using System.Data using System.Data.SqlClient Table name constants public const String ORDERS_TABLE Orders public const String ORDERDETAILS_TABLE OrderDetails Field name constants for Orders table public const String ORDERID_FIELD OrderlD public const String CUSTOMERID_FIELD CustomerlD public const String EMPLOYEEID_FIELD EmployeeID public const String ORDERDATE_FIELD OrderDate public const String REQUIREDDATE_FIELD RequiredDate public const String SHIPPEDDDATE_FIELD ShippedDate public const String SHIPVIA_FIELD ShipVia public const String FREIGHT_FIELD Freight public const String SHIPNAME_FIELD ShipName public const .