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translation. This means that computers sitting behind these devices cannot be easily addressable

from outside the company network. In addition, as the number of public IPv4 addresses dwindles,

more connections are dynamically allocated an IP address. This makes hosting an application

within the company network that is publicly accessible almost impossible.

The Service Bus allows a service to be registered at a specific publicly addressable URL via the

service registry. Requests made to this URL are directed to the service via an existing outbound

connection made by the service itself. Working with the Service Bus can be as simple as changing

your existing WCF bindings across to the new relay bindings. As part of running your service it

registers with the service registry and initiates the outbound connection required for all further

communications.

access control service

Where an organization wants to integrate multiple cloud-based applications and/or an on-premise

application there needs to be some way of controlling who (authentication) has access to particular

resources (authorization). This is the function of the Access Control Service (ACS). Though still

in its infancy, the ACS is capable of verifying a user’s identity through the validation of input

claims, performing claims translation, and the supply of output claims for specific applications. For

example, you could sign into an application providing your e-mail address and a password. These

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input claims would be used to authenticate you, as well as determine that you belong in the fancy-

hat group in application xyz that you are trying to access. The output claims may consist of your

e-mail address and the fancy-hat group. Note that because there is a previously established trust

relationship between application xyz and ACS (validated through signing of the output claims),

application xyz can trust the output claims.

suMMary

In this chapter you learned about the Windows Azure Platform and how it represents Microsoft’s

entry into the cloud computing space. Using Visual Studio 2010, you can adapt an existing, or

create a new, application or service for hosting in the cloud. The local Development Storage and

Fabric provide a great local testing solution, which means when you publish your application to

Windows Azure you can be confident that it will work without major issues.

Even if you don’t want to migrate your entire application into the cloud, you can use SQL Azure and

the AppFabric offerings to host your data, address connectivity challenges, or unify your application

security.

PART VI

data

. chaPter 26: Visual Database Tools

. chaPter 27: Datasets and Data Binding

. chaPter 28: Language Integrated Queries (LINQ)

. chaPter 29: The ADO NET Entity Framework

. chaPter 30: Reporting

26

Visual Database Tools

what’s in this chaPter?

.

Understanding the data-oriented tool windows within

Visual Studio 2010

.

Creating and designing databases

.

Navigating your data sources

.

Entering and previewing data using Visual Studio 2010

Database connectivity is essential in almost every application you create, regardless of whether

it’s a Windows-based program or a web site or service. When Visual Studio .NET was first

introduced, it provided developers with a great set of options to navigate to the database files

on their file systems and local servers, with a Server Explorer, data controls, and data-bound

components. The underlying .NET Framework included ADO.NET, a retooled database engine

that is more suited to the way applications are built today.

Visual Studio 2010 took those features and smoothed out the kinks, adding tools and

functionality to the IDE to give you more direct access to the data in your application. This

chapter looks at how you can create, manage, and consume data using the various tool

windows provided in Visual Studio 2010. These can be collectively referred to as the Visual

Database Tools.

database windows in Visual studio 2010

A number of windows specifically deal with databases and their components. From the

Data Sources window that shows project-related data files and the Data Connections

node in the Server Explorer, to the Database Diagram Editor and the visual designer for

database schemas, you’ll find most of what you need directly within the IDE. In fact, it’s

unlikely that you’ll need to venture outside of Visual Studio to work with your data.

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chaPter 26 ViSuAl dATAbASe ToolS

Figure 26-1 shows the Visual Studio 2010 IDE with a current database-editing session. Notice how

the windows, toolbars, and menus all update to match the particular context of editing a database

table. In the main area is the list of columns belonging to the table, a Table Designer menu has been

added, and there is a Column Properties editing region below. The normal Properties tool window

contains the properties for the current table. The next few pages take a look at each of these

windows and describe their purposes so you can use them effectively.

fiGure 26-1

server explorer

In Chapter 12, you saw how the Server Explorer can be used to navigate the components that make

up your system (or indeed the components of any server to which you can connect). One component

of this tool window that was omitted from that discussion is the Data Connections node. Through

this node, Visual Studio 2010 provides a significant subset of the functionality that is available

through other products, such as SQL Server Management Studio, for creating and modifying

databases.

Figure 26-1 shows the Server Explorer window with an active database connection

(AdventureWorksLT2009_Data.mdf) and another database that Visual Studio is not currently

connected to (CRM.mdf). The database icon displays whether or not you are actively connected

to the database, and contains a number of child nodes dealing with the typical components of a

modern database, such as Tables, Views, and Stored Procedures. Expanding these nodes lists the

specific database components along with their details. For example, the Tables node contains a

Database Windows in Visual studio 2010 .

551

node for the Customer table, which in turn has nodes for each of the columns, such as CustomerID,

FirstName, and LastName. Clicking these nodes enables you to quickly view the properties within

the Properties tool window. This is the default database view; you can switch to either Object Type

or Schema view by selecting Change View, followed by the view to change to, from the right-click

context menu off the database node. Each of these views simply groups the information about the

database in a different hierarchy.

To add a new database connection to the Server Explorer window, click the Connect to Database

button at the top of the Server Explorer (third icon in from the left), or right-click the Data

Connections root node and select the Add Connection command from the context menu.

If this is the first time you have added a connection, Visual Studio asks you what type of data

source you are connecting to. Visual Studio 2010 comes packaged with a number of Data Source

connectors, including Access, SQL Server, and Oracle, as well as a generic ODBC driver. It also

includes a data source connector for Microsoft SQL Server Database File and Microsoft SQL Server

Compact databases.

The Database File option was introduced in SQL Server 2005 and borrows from the easy

deployment model of its lesser cousins, Microsoft Access and MSDE. With SQL Server Database

File, you can create a flat file for an individual database. This means you don’t need to attach it to

a SQL Server instance, and it’s highly portable — you simply deliver the .mdf file containing the

database along with your application. Alternatively, using a SQL Server Compact (SSC) database

can significantly reduce the system requirements for your application. Instead of requiring an

instance of SQL Server to be installed, the SSC runtime

can be deployed alongside your application.

Once you’ve chosen the data source type to use, the

Add Connection dialog appears. Figure 26-2 shows this

dialog for a SQL Server Database File connection, with

the settings that are appropriate to that data source type.

You are taken directly to this dialog if you already have

data connections defined in Visual Studio.

The Change button takes you to the Data Sources

page, enabling you to add different types of database

connections to your Visual Studio session. Note how

easy it is to create a SQL Server Database File. Just type

or browse to the location where you want the file and

specify the database name for a new database. If you

want to connect to an existing database, use the Browse

button to locate it on the file system.

Generally, the only other task you need to perform is to

specify whether your SQL Server configuration is using

Windows or SQL Server Authentication. The default

installation of Visual Studio 2010 includes an installation of SQL Server 2005 Express, which uses

Windows Authentication as its base authentication model.

fiGure 26-2

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chaPter 26 ViSuAl dATAbASe ToolS

The Test Connection button displays an error message if you try to connect to

a new database. This is because it doesn’t exist until you click OK, so there’s

nothing to connect to!

When you click OK, Visual Studio attempts to connect to the database. If successful, it adds it to

the Data Connections node, including the children nodes for the main data types in the database,

as discussed earlier. Alternatively, if the database doesn’t exist, Visual Studio prompts you asking

if it should go ahead and create it. You can also create a new database by selecting the Create New

SQL Server Database item from the right-click menu off the Data Connections node in the Server

Explorer.

Table editing

The easiest way to edit a table in the database is to

double-click its entry in the Server Explorer. An editing

window is then displayed in the main workspace,

consisting of two components. The top section is

where you specify each field name, data type, and key

information such as length for text fields, and whether

the field is nullable.

Right-clicking a field gives you access to a set of

commands that you can perform against that field, as

shown in Figure 26-3 . This context menu contains the

same items as the Table Designer menu that is displayed

while you’re editing a table, but it is usually easier to use

the context menu because you can clearly see which field

you’ re modifying.

The lower half of the table editing workspace contains

the Column Properties window for the currently

selected column. Unlike the grid area that simply

lists the Column Name, Data Type, and whether

the column allows nulls, the column properties area

allows you to specify all of the available properties

for the particular Data Source type.

Figure 26-4 shows a sample Column Properties window

for a field, CustomerID, that has been defined with an

identity clause that is automatically incremented by 1

for each new record added to the table.

relationship editing

Most databases that are likely to be used by your

.NET solutions are relational in nature, which means

fiGure 26-3

fiGure 26-4

Database Windows in Visual studio 2010 .

553

you connect tables together by defining

relationships. To create a relationship, open

one of the tables that will be part of the

relationship and click the Relationships

button on the toolbar, or use the Table

Designer . Relationships menu command.

The Foreign Key Relationships dialog is

displayed (see Figure 26-5), containing

any existing relationships that are bound

to the table you selected.

Click the Add button to create a new

relationship, or select one of the existing

relationships to edit. Locate the Tables and

Columns Specification entry in the property

grid and click its associated ellipsis to set the

tables and columns that should connect to

each other. In the Tables and Columns dialog,

shown in Figure 26-6, first choose which

table contains the primary key to which

the table you selected will connect. Note that

for new relationships the Foreign key table

field is populated with the current table name

and cannot be changed.

Once you have the Primary key table, you then connect the fields in each table that should bind to

each other. You can add multiple fields to the relationship by clicking the blank row that is added as

you add the previous field. When you are satisfied with the relationship settings, click OK to save it

and return to the Foreign Key Relationships dialog.

Views

Views are predefined queries that can appear like tables to your application and can be made up of

multiple tables. Use the Data . Add New . View menu command or right-click the Views node in

Server Explorer and choose Add New View from the context menu.

The first task is to choose which tables, other views, functions, and synonyms will be included in

the current view. When you’ve chosen which components will be added, the View editor window is

displayed (see Figure 26-7). This editor should be familiar to anyone who has worked with a visual

database designer such as Access. The tables and other components are visible in the top area,

where you can select the fields you want included. The top area also shows connections between

any functions and tables. The View in Figure 26-7 connects three tables by linking all rows in the

Customer table with the CustomerAddress and Address tables. Figure 26-7 also shows that by

right-clicking the connector between tables you can change the type of join used. If you need to

add additional tables, right-click the design surface and select Add Table.

fiGure 26-5

fiGure 26-6

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chaPter 26 ViSuAl dATAbASe ToolS

fiGure 26-7

The middle area shows a tabular representation of your current selection, and adds columns for