用于实现随机取数据。在DataClasses.designer.cs内加入如下代码：

[System.Data.Linq.Mapping.DatabaseAttribute(Name="XJW")]
public partial class GaDB : System.Data.Linq.DataContext
{
        [Function(Name = "NewId", IsComposable = true)]
        public Guid NewId()
        {
                return (Guid)ExecuteMethodCall(this, MethodInfo.GetCurrentMethod() as MethodInfo).ReturnValue;
        }
}

调用：

var query = XJW.DB.TableName.OrderBy(t=>XJW.DB.NewId());