Which one of these samples it the correct way to close the connection using Command Behavior?

• A. using (SqlDataReader rdr = new SqlDataReader())
  {
  string sql = @"sql statement";
  SqlConnection conn = connection.GetConnection();
  SqlCommand cmd = new SqlCommand(sql, conn);
  SqlDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
  Console.WriteLine("{0}", rdr);
  }
• B. SqlDataReader rdr = new SqlDataReader(); string sql = @"sql statement"; SqlConnection conn = connection.GetConnection(); SqlCommand cmd = new SqlCommand(sql, conn); SqlDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection); Console.WriteLine("{0}", rdr);
• C. SqlDataReader rdr = new SqlDataReader(); string sql = @"sql statement"; SqlConnection conn = connection.GetConnection(); SqlCommand cmd = new SqlCommand(sql, conn); SqlDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection); conn.Close(); Console.WriteLine("{0}", rdr);
• D. SqlDataReader rdr = new SqlDataReader(); string sql = @"sql statement"; SqlConnection conn = connection.GetConnection(); SqlCommand cmd = new SqlCommand(sql, conn); SqlDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection); rdr.Close(); Console.WriteLine("{0}", rdr);

You use Microsoft Visual Studio 2010 and Microsoft ADO.NET Framework 4.0 to create an application.
The application connects to a Microsoft SQL Server 2008 database.
You use the ADO.NET LINQ to SQL model to retrieve data from the database. You use stored procedures
to return multiple result sets.
You need to ensure that the result sets are returned as strongly typed values. What should you do?

• A. Apply the ResultTypeAttribute to the stored procedure function and directly access the strongly typed object from the results collection.
• B. Apply the ParameterAttribute to the stored procedure function. Use the GetResult<TElement> method to obtain an enumerator of the correct type.
• C. Apply the FunctionAttribute and ParameterAttribute to the stored procedure function and directly access the strongly typed object from the results collection.
• D. Apply the FunctionAttribute and ResultTypeAttribute to the stored procedure function. Use the GetResult<TElement> method to obtain an enumerator of the correct type.

You use Microsoft Visual Studio 2010 and Microsoft .NET Framework 4.0 to create an application.
The application connects to a Microsoft SQL Server database.
The application uses a DataTable named OrderDetailTable that has the following columns:
-ID
-OrderID
-ProductID
-Quantity
-LineTotal
Some records contain a null value in the LineTotal field and 0 in the Quantity field. You write the following code segment. (Line numbers are included for reference only.)
01 DataColumn column = new DataColumn("UnitPrice", typeof(double));
02 ...
03 OrderDetailTable.Columns.Add(column);
You need to add a calculated DataColumn named UnitPrice to the OrderDetailTable object.
You also need to ensure that UnitPrice is set to 0 when it cannot be calculated.
Which code segment should you insert at line 02?

• A. column.Expression = "iif(Quantity > 0, LineTotal/Quantity, 0)";
• B. column.Expression = "if(Quantity > 0, LineTotal/Quantity, 0)";
• C. column.Expression = "LineTotal/Quantity";
• D. column.Expression = "LineTotal/ISNULL(Quantity, 1)";

You use Microsoft Visual Studio 2010 and Microsoft .NET Framework 4.0 to create an application. You use the ADO.NET Entity Framework to model entities. You write the following code segment. (Line numbers are included for reference only.)
01 AdventureWorksEntities context = new AdventureWorksEntities("http://
localhost:1234/AdventureWorks.svc");
02 ...
03 var q = from c in context.Customers
04 where c.City == "London"
05 orderby c.CompanyName
06 select c;
You need to ensure that the application meets the following requirements:
-Compares the current values of unmodified properties with values returned from the data source.
-Marks the property as modified when the properties are not the same. Which code segment should you insert at line 02?

• A. context.MergeOption = MergeOption.PreserveChanges;
• B. context.MergeOption = MergeOption.AppendOnly;
• C. context.MergeOption = MergeOption.NoTracking;
• D. context.MergeOption = MergeOption.OverwriteChanges;

You use Microsoft Visual Studio 2010 and Microsoft .NET Framework 4.0 to create an application. The application contains the following XML document:
<bib> <book title="TCP/IP Illusrated" year="1994">
<author>Author1</author>
</book>
<book title="Programming in UNIX" year="1992">
<author>Author1</author>
<author>Author2</author>
<author>Author3</author>
</book>
<book title="Data on the web" year="2000">
<author>Author4</author>
<author>Author3</author>
</book> </bib>
You add the following code fragment. (Line numbers are included for reference only.)
01 public IEnumerable<XElement> GetBooks(string xml)
02 {
03 XDocument doc = XDocument.Parse(xml);
04 ...
05 }
You need to return a list of book XML element that are authored by Author1. Which code segment should you insert at line 04?

• A. return doc.Element("bib").Elements() .SelectMany(el => el.Elements() .Where(e2 => (string)e2 == "Author1"));
• B. return doc.Element("bib").Elements() .SelectMany(el => el.Elements() .Where(e2 => e2.Equals(new XElement("author", "Author1"))));
• C. return doc.Elements("bib").Elements()
  .Where(e1 => e1.Elements().Any(e2 => e2.Equals(new XElement("author", "Author1"))));
• D. return doc.Elements("bib").Elements() .Where(e1 => e1.Elements().Any(e2 => (string)e2 == "Author1"));