в 15:31, 26 мая 2010

2010-05-26T15:31:19Z

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2010-05-26T11:42:37Z

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==More than one Relations==

<source lang="csharp">

using System;
using System.Data;
using System.Data.SqlClient;
using System.Collections.Generic;
using System.Text;
class Program {
static void Main(string[] args) {
SqlConnection thisConnection = new SqlConnection(@"Server=(local)\sqlexpress;Integrated Security=True;" +
"Database=northwind");
DataSet thisDataSet = new DataSet();
SqlDataAdapter custAdapter = new SqlDataAdapter("SELECT * FROM Customers", thisConnection);
custAdapter.Fill(thisDataSet, "Customers");
SqlDataAdapter orderAdapter = new SqlDataAdapter("SELECT * FROM Orders", thisConnection);
orderAdapter.Fill(thisDataSet, "Orders");
SqlDataAdapter detailAdapter = new SqlDataAdapter("SELECT * FROM [Order Details]", thisConnection);
detailAdapter.Fill(thisDataSet, "Order Details");
SqlDataAdapter prodAdapter = new SqlDataAdapter("SELECT * FROM Products", thisConnection);
prodAdapter.Fill(thisDataSet, "Products");
DataRelation custOrderRel = thisDataSet.Relations.Add("CustOrders",
thisDataSet.Tables["Customers"].Columns["CustomerID"],
thisDataSet.Tables["Orders"].Columns["CustomerID"]);
DataRelation orderDetailRel = thisDataSet.Relations.Add("OrderDetail",
thisDataSet.Tables["Orders"].Columns["OrderID"],
thisDataSet.Tables["Order Details"].Columns["OrderID"]);
DataRelation orderProductRel = thisDataSet.Relations.Add(
"OrderProducts", thisDataSet.Tables["Products"].Columns["ProductID"],
thisDataSet.Tables["Order Details"].Columns["ProductID"]);
foreach (DataRow custRow in thisDataSet.Tables["Customers"].Rows) {
Console.WriteLine("Customer ID: " + custRow["CustomerID"]);
foreach (DataRow orderRow in custRow.GetChildRows(custOrderRel)) {
Console.WriteLine("\tOrder ID: " + orderRow["OrderID"]);
Console.WriteLine("\t\tOrder Date: " + orderRow["OrderDate"]);
foreach (DataRow detailRow in
orderRow.GetChildRows(orderDetailRel)) {
Console.WriteLine("\t\tProduct: " +
detailRow.GetParentRow(orderProductRel)["ProductName"]);
Console.WriteLine("\t\tQuantity: " + detailRow["Quantity"]);
}
}
}
thisConnection.Close();
}
}

</source>

==Setting the Nested property of a DataRelation to true==

<source lang="csharp">
using System;
using System.Data;
using System.Data.SqlClient;
class NestedXml
{
public static void Main()
{
SqlConnection mySqlConnection =new SqlConnection("server=(local)\\SQLEXPRESS;database=MyDatabase;Integrated Security=SSPI;");
SqlCommand mySqlCommand = mySqlConnection.CreateCommand();
mySqlCommand.rumandText =
"SELECT TOP 2 EmployeeID, CompanyName " +
"FROM Employee " +
"ORDER BY EmployeeID;" +
"SELECT DeptID, EmployeeID, City " +
"FROM Dept " +
"WHERE EmployeeID IN (" +
" SELECT TOP 2 EmployeeID " +
" FROM Employee " +
" ORDER BY EmployeeID " +
")";
SqlDataAdapter mySqlDataAdapter = new SqlDataAdapter();
mySqlDataAdapter.SelectCommand = mySqlCommand;
DataSet myDataSet = new DataSet();
mySqlConnection.Open();
int numberOfRows = mySqlDataAdapter.Fill(myDataSet);
Console.WriteLine("numberOfRows = " + numberOfRows);
mySqlConnection.Close();
DataTable customersDT = myDataSet.Tables["Table"];
DataTable ordersDT = myDataSet.Tables["Table1"];
DataRelation customersDeptDataRel =
new DataRelation(
"EmployeeDept",
customersDT.Columns["EmployeeID"],
ordersDT.Columns["EmployeeID"]
);
myDataSet.Relations.Add(
customersDeptDataRel
);
myDataSet.WriteXml("nonNestedXmlFile.xml");
myDataSet.Relations["EmployeeDept"].Nested = true;
myDataSet.WriteXml("nestedXmlFile.xml");
}
}

</source>

==Set up DataRelation ==

<source lang="csharp">

using System;
using System.Data;
using System.Data.SqlClient;
using System.Collections.Generic;
using System.Text;
class Program {
static void Main(string[] args) {
SqlConnection thisConnection = new SqlConnection(
@"Server=(local)\sqlexpress;Integrated Security=True;" +
"Database=northwind");
SqlDataAdapter thisAdapter = new SqlDataAdapter(
"SELECT CustomerID, CompanyName FROM Customers", thisConnection);
SqlCommandBuilder thisBuilder = new SqlCommandBuilder(thisAdapter);
DataSet thisDataSet = new DataSet();
SqlDataAdapter custAdapter = new SqlDataAdapter(
"SELECT * FROM Customers", thisConnection);
SqlDataAdapter orderAdapter = new SqlDataAdapter(
"SELECT * FROM Orders", thisConnection);
custAdapter.Fill(thisDataSet, "Customers");
orderAdapter.Fill(thisDataSet, "Orders");
DataRelation custOrderRel = thisDataSet.Relations.Add("CustOrders",
thisDataSet.Tables["Customers"].Columns["CustomerID"],
thisDataSet.Tables["Orders"].Columns["CustomerID"]);
foreach (DataRow custRow in thisDataSet.Tables["Customers"].Rows) {
Console.WriteLine("Customer ID: " + custRow["CustomerID"] +
" Name: " + custRow["CompanyName"]);
foreach (DataRow orderRow in custRow.GetChildRows(custOrderRel)) {
Console.WriteLine(" Order ID: " + orderRow["OrderID"]);
}
}
thisConnection.Close();
}
}

</source>

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в 15:31, 26 мая 2010

Admin: 1 версия