Union in Data

Question

Hi.... I am working in ADO.NET and face a problem in Join and Union. How can we use join and union in ADO.NET ?

Jignesh Trivedi · Answer

hi you can join two table using LINQ to DataTable. DataTable orders = ds.Tables[SalesOrderHeader]; DataTable details = ds.Tables[SalesOrderDetail]; var query = from order in orders.AsEnumerable() join detail in details.AsEnumerable() on order.Field (SalesOrderID) equals detail.Field (SalesOrderID) where order.Field (OnlineOrderFlag) == true && order.Field (OrderDate).Month == 8 select new { SalesOrderID = order.Field (SalesOrderID) SalesOrderDetailID = detail.Field (SalesOrderDetailID) OrderDate = order.Field (OrderDate) ProductID = detail.Field (ProductID) }; DataTable orderTable = query.CopyToDataTable(); union two table use datatable.merge(datatable2) more detail please refer http://msdn.microsoft.com/en-us/library/bb386921.aspx http://msdn.microsoft.com/en-us/library/system.data.datatable.merge.aspx

Pravin More · Answer

HI Rajesh Below are the syntax to use Join and Union. JOIN Select * from Table1 t1 join Table2 t2 on t1.Column1=t2.Column1 Union Select Column1Column2 from Table1 Union Select Column1Column2 from Table2 Thanks Pravin.