Question

我正在使用C＃+ .Net 3.5 + VSTS 2008 + ADO.Net + SQL Server 2008.我在SQL Server中有两个相关的表（外键关系）。我想将两个表加载为数据集中的两个数据表。有没有这样做的参考代码？

提前谢谢，乔治

Answer 1

试试这个

Dim myAdapter as SqlDataAdapter = new SqlDataAdapter(
      “SELECT * FROM Customers; SELECT * FROM Orders“, connection)

myAdapter.Fill(dsTables)
dsTables.Tables(0).TableName = “Customers“)
dsTables.Tables(1).TableName = “Orders“)

http://pietschsoft.com/post/2004/08/22/Fill-DataSet-with-multiple-Tables-and-update-them-with-DataAdapter.aspx

Answer 2

乔治，

您能否澄清一下您的问题 - 是关于填充数据集中的多个表格，还是仅填写特定的表格。

就加载多个表而言，您可以参考以下代码（此代码在MSDN http://msdn.microsoft.com/en-us/library/5fd1ahe2.aspx处可用）：

static void Main()
 {
   DataSet dataSet = new DataSet();

    DataTable customerTable = new DataTable();
    DataTable productTable = new DataTable();

    // This information is cosmetic, only.
    customerTable.TableName = "Customers";
    productTable.TableName = "Products";

    // Add the tables to the DataSet:
    dataSet.Tables.Add(customerTable);
    dataSet.Tables.Add(productTable);

    // Load the data into the existing DataSet. 
    DataTableReader reader = GetReader();
    dataSet.Load(reader, LoadOption.OverwriteChanges,
        customerTable, productTable);

    // Print out the contents of each table:
    foreach (DataTable table in dataSet.Tables)
       {
        PrintColumns(table);
        }

    Console.WriteLine("Press any key to continue.");
    Console.ReadKey();
}

private static DataTable GetCustomers()
{
    // Create sample Customers table.
    DataTable table = new DataTable();
    table.TableName = "Customers";

    // Create two columns, ID and Name.
    DataColumn idColumn = table.Columns.Add("ID", typeof(int));
    table.Columns.Add("Name", typeof(string));

    // Set the ID column as the primary key column.
    table.PrimaryKey = new DataColumn[] { idColumn };

    table.Rows.Add(new object[] { 0, "Mary" });
    table.Rows.Add(new object[] { 1, "Andy" });
    table.Rows.Add(new object[] { 2, "Peter" });
    table.AcceptChanges();
    return table;
}

private static DataTable GetProducts()
{
    // Create sample Products table.
    DataTable table = new DataTable();
    table.TableName = "Products";

    // Create two columns, ID and Name.
    DataColumn idColumn = table.Columns.Add("ID",
        typeof(int));
    table.Columns.Add("Name", typeof(string));

    // Set the ID column as the primary key column.
        table.PrimaryKey = new DataColumn[] { idColumn };

    table.Rows.Add(new object[] { 0, "Wireless Network Card" });
    table.Rows.Add(new object[] { 1, "Hard Drive" });
    table.Rows.Add(new object[] { 2, "Monitor" });
    table.Rows.Add(new object[] { 3, "CPU" });
    table.AcceptChanges();
    return table;
}

private static void PrintColumns(DataTable table)
{
    Console.WriteLine();
    Console.WriteLine(table.TableName);
    Console.WriteLine("=========================");
    // Loop through all the rows in the table:
    foreach (DataRow row in table.Rows)
    {
        for (int i = 0; i < table.Columns.Count; i++)
        {
            Console.Write(row[i] + " ");
        }
        Console.WriteLine();
    }
}

private static DataTableReader GetReader()
{
    // Return a DataTableReader containing multiple
    // result sets, just for the sake of this demo.
    DataSet dataSet = new DataSet();
    dataSet.Tables.Add(GetCustomers());
    dataSet.Tables.Add(GetProducts());
    return dataSet.CreateDataReader();
}

以下是管理数据集中父子关系的代码

Imports System.Data
Imports System.Data.SqlClient
Imports System.Configuration

Public Class DataRelation
  Inherits System.Web.UI.Page

  Protected lblDisplay As System.Web.UI.WebControls.Label

  Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
    Dim objConn As SqlConnection
    Dim da As SqlDataAdapter
    Dim ds As DataSet
    Dim dtrParent As DataRow
    Dim dtrChild As DataRow

    objConn = New SqlConnection(ConfigurationSettings.Appsettings("NorthwindConnection"))
    da = New SqlDataAdapter("SELECT * FROM Categories", objConn)
    ds = New DataSet()
    Try
      objConn.Open()
      da.Fill( ds,"Categories")
      da.SelectCommand = New SqlCommand("SELECT * FROM Products", objConn)
      da.Fill(ds, "Products")
    Catch exc As SqlException
      Response.Write(exc.ToString())
    Finally
      objConn.Dispose()
    End Try 
    'Create the Data Relationship
    ds.Relations.Add("Cat_Prod",ds.Tables("Categories").Columns("CategoryID"), _
                            ds.Tables("Products").Columns("CategoryID"))

    'Display the Category and Child Products Within
    For each dtrParent in ds.Tables("Categories").Rows
      lblDisplay.Text &= "<h3>" & dtrParent("CategoryName") & "</h3><ul>"
      For each dtrChild in dtrParent.GetChildRows("Cat_Prod")
        lblDisplay.Text &= "<li>" & dtrChild("ProductName") & "</li>"
      Next
      lblDisplay.Text &= "</ul>"
    Next
  End Sub

End Class

您可以在here

上找到进一步的解释

Answer 3

以下是有关如何使用LINQ查询加载DataSet的示例代码这里有2张表有关系。 “dc”是数据上下文。

            var query = dc.GetTable<Media>().Where(s => s.MediaID == new Guid("A72AA79A-6C40-4D6B-A826-241553FECDFE"));
            var query1 = dc.GetTable<MediaVersion>().Where(s => s.MediaID == new Guid("A72AA79A-6C40-4D6B-A826-241553FECDFE"));
            var query2 = dc.GetTable<RootPath>().Where(s => s.RootPathID == new Guid("62145B2C-BA36-4313-8CA2-0F224F8FE7E8"));


            SqlCommand cmd = dc.GetCommand(query) as SqlCommand;
            //Load first
            SqlDataAdapter ada = new SqlDataAdapter(cmd);
            DataSet ds = new DataSet();
            ada.Fill(ds, "Media");
            //Load second
            cmd = dc.GetCommand(query1) as SqlCommand;
            ada.SelectCommand = cmd;
            ada.Fill(ds, "MediaVersion");
            ds.Relations.Add("Med_MedVer", ds.Tables["Media"].Columns["MediaID"],
                       ds.Tables["MediaVersion"].Columns["MediaID"]);

            //Load third independent table
            cmd = dc.GetCommand(query2) as SqlCommand;
            ada.SelectCommand = cmd;
            ada.Fill(ds, "RootPath");

如何让DataSet返回两个相关的表？

3 个答案: