帮忙看下哪有语法错误～
创—ataRelation对象来表示数据库中的两个关系，代码如下：


using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Text; //用于字符串处理
using System.Data.SqlClient;　//用于数据处理等


public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
UpdateDetailsGrid( );

DataSet ds = CreateDataSet( );
GridView1.DataSource = ds.Tables[0];
GridView1.DataBind( );

//创—ataView,并将其绑定到GridView
DataView detailsView = new DataView(ds.Tables[1]);
DetailsGridView.DataSource = detailsView;
Session[ "DetailsView "] = detailsView;
DetailsGridView.DataBind( );

//将OrderRelationsGridView绑定到关系集合
OrderRelationsGridView.DataSource = ds.Relations;
OrderRelationsGridView.DataBind( );
}
}
//获取订单细节
public void OnSelectedIndexChangedHandler(object sender, EventArgs e)
{
UpdateDetailsGrid( );
}

private void UpdateDetailsGrid( )
{
int index = GridView1.SelectedIndex;
if (index != -1)
{
//从GridView中获取订单号
DataKey key = GridView1.DataKeys[index];
int orderID = (int) key.Value;

DataView detailsView = (DataView)Session[ "detailsView "];
detailsView.RowFilter = "OrderID= " + orderID;
DetailsGridView.DataSource = detailsView;
DetailsGridView.DataBind( );
OrderDetailsPanel.Visible = true;
}
else
{
OrderDetailsPanel.Visible = false;
}
}
private DataSet CreateDataSet( )
{
//使用连接字符串连接到Orders数据库
string connectionString = "Data Source=CHENGPIN-FC27ED\\SQLEXPRESS;Initial Catalog=Northwind;Integrated Security=True ";

//创建连接对象，初始化连接字符串并打开连接
System.Data.SqlClient.SqlConnection connection = new System.Data.SqlClient.SqlConnection(connectionString);

connection.Open( );

//创建Sqlcommand对象，并为其设置连接
System.Data.SqlClient.SqlCommand command=new System.Data.SqlClient.SqlCommand( );
command.Connection=connection;

StringBuilder s = new StringBuilder( "select OrderID,c.CompanyName,c.ContactName, ");
s.Append( " c.ContactTitle,c.Phone,orderDate ");
s.Append( " from orders o ");
s.Append( "join customers c on c.CustomerID = o.CustomerID ");

//为select语句设置命令文本
command.CommandText=s.ToString( );

//创建SqlDataAdapter,并设置其命令对象
//为bugs添加表映射
SqlDataAdapter dataAdapter=new SqlDataAdapter( );
dataAdapter.SelectCommand=command;
dataAdapter.TableMappings.Add( "Table ", "Orders ");

//创—ataSet,并使用DataAdapter填充

DataSet dataSet = new DataSet( );
dataAdapter.Fill(dataSet);

//为订单创建第二个命令对象
System.Data.SqlClient.SqlCommand command2=new System.Data.SqlClient.SqlCommand( );
command2.Connection=connection;

//确认添加了一个列，这样您可以为产品创建一个关系
StringBuilder s2=new StringBuilder( "select od.OrderID,OrderDate,p.ProductID, ");
s.Append( "ProductName,od.UnitPrice,Quantity ");
s.Append( " from Orders o ");
s.Append( " join [Order Details] od on o.orderid = od.orderid ");
s.Append( " join products p on p.productID = od.productid ");
command2.CommandText=s2.ToString( );

//创建第二个SqlDataAdapter
//添加命令和表映射，然后使用第二个SqlDataAdapter填充DataSet
SqlDataAdapter dataAdapter2=new SqlDataAdapter( );
dataAdapter2.SelectCommand=command2;
dataAdapter2.TableMappings.Add( "Table ", "Order Details ");


源错误行：
　　　　dataAdapter2.Fill(dataSet);　　



　　　　//为产品创建第三个命令对象
System.Data.SqlClient.SqlCommand command3=new System.Data.SqlClient.SqlCommand( );
command3.Connection=connection;

string strCommand3= "Select ProductID,ProductName from Products ";
command3.CommandText=strCommand3;

//创建第三个SqlDataAdapter,然后添加命令和表映射
//使用第二个SqlDataAdapter填充DataSet
SqlDataAdapter dataAdapter3=new SqlDataAdapter( );
dataAdapter3.SelectCommand=command3;
dataAdapter3.TableMappings.Add( "Table ", "Products ");
dataAdapter3.Fill(dataSet);

//声明DataRelation和DataColumn对象
System.Data.DataRelation dataRelation;
System.Data.DataColumn dataColumn1;

System.Data.DataColumn dataColumn2;

//为了创建关系,设置数据列
//该关系使用了OrderID,它位于Orders和Order Details之间
dataColumn1=dataSet.Tables[ "Orders "].Columns[ "OrderID "];
dataColumn2=dataSet.Tables[ "Order Details "].Columns[ "OrderID "];

dataRelation=new System.Data.DataRelation( "OrdersToDetails ",dataColumn1,dataColumn2);

//为 DataSet设置新的DataRelation
dataSet.Relations.Add(dataRelation);

//为了在Order Details 和Products之间创建关系，须重用DataColumn和DataRelation对象
dataColumn1=dataSet.Tables[ "Products "].Columns[ "ProductID "];
dataColumn2=dataSet.Tables[ "Order Details "].Columns[ "ProductID "];
dataRelation=new System.Data.DataRelation( "ProductIDToName ",dataColumn1,dataColumn2);

//为DataSet添加关系
dataSet.Relations.Add(dataRelation);

return dataSet;
} //CreateDataSet方法结束

}　　　//类结束


错误信息：

', ' 附近有语法错误。
说明: 执行当前 Web 请求期间，出现未处理的异常。请检查堆栈跟踪信息，以了解有关该错误以及代码中导致错误的出处的详细信息。

异常详细信息: System.Data.SqlClient.SqlException: ', ' 附近有语法错误。

源错误:


行 110: dataAdapter2.SelectCommand=command2;
行 111: dataAdapter2.TableMappings.Add( "Table ", "Order Details ");
行 112: dataAdapter2.Fill(dataSet);
行 113:
行 114: //为产品创建第三个命令对象


源文件: d:\My Documents\Visual Studio 2005\WebSites\StoredProcedures\Default.aspx.cs 行: 112



[解决办法]
StringBuilder s2=new StringBuilder( "select od.OrderID,OrderDate,p.ProductID, ");
s.Append( "ProductName,od.UnitPrice,Quantity ");
s.Append( " from Orders o ");
s.Append( " join [Order Details] od on o.orderid = od.orderid ");
s.Append( " join products p on p.productID = od.productid ");
command2.CommandText=s2.ToString( );
改为

StringBuilder s2=new StringBuilder();
s2.Append( "select od.OrderID,OrderDate,p.ProductID, ");
s2.Append( "ProductName,od.UnitPrice,Quantity ");
s2.Append( " from Orders o ");
s2.Append( " join [Order Details] od on o.orderid = od.orderid ");

s2.Append( " join products p on p.productID = od.productid ");
command2.CommandText=s2.ToString( );

[解决办法]
1. s.Append( "ProductName,od.UnitPrice,Quantity ");
ProductName和Quantity是哪个表的字段不明确?
2.
s.Append( " join [Order Details] od on o.orderid = od.orderid ");
s.Append( " join products p on p.productID = od.productid ");
==>
s.Append( " left join [Order Details] od on o.orderid = od.orderid ");
s.Append( " left join products p on p.productID = od.productid ");
[解决办法]
单步调式得到s2的完整的值 放在SQL里面看