Click here to close now.




















Welcome!

Microsoft Cloud Authors: Adine Deford, Elizabeth White, the Editor, Michael Krems, Xenia von Wedel

Related Topics: Microsoft Cloud

Microsoft Cloud: Article

SQL Server Web Services

Create and host XML Web services inside SQL Server 2005

These days, applications built around a service-oriented architecture (SOA) are all the rage. Complex systems can be written as a collection of services that communicate with each other through standard protocols. When implemented properly, these systems can become immensely flexible, scalable, and easy to maintain. The most common SOA designs utilize Web services as the communications medium, because they can be created and consumed by disparate systems and platforms. This highly useful capability has made Web services a very important part of today's information systems.

Up until now, the classic Microsoft implementation of a Web service involved a back-end database server running SQL Server 2000 and a front-end Web server running a .NET Web service application on IIS. Now that SQL Server 2005 is here, we have an additional option: we can create and host Web services using SQL Server alone. In this scenario, no Web server is needed. When running on Windows Server 2003 or Windows XP with Service Pack 2, IIS is not needed either. These operating systems provide the HTTP API, also known as HTTP.SYS, which SQL Server uses to provide native Web service functionality.

In this article I will show how to create a Web service inside SQL Server. I will show how to define the service and how to access it from a .NET client application. Along the way, we will see how incredibly flexible SQL Server's Web service support is. Hopefully, we will also gain an appreciation of how capable a tool SQL Server 2005 has become. Let's get started.

Endpoints
SQL Server 2005 provides Web services through endpoints. Endpoints define the properties of a connection, which can use either the HTTP or the TCP protocol. They can provide support for SOAP, Service Broker, and Database Mirroring. As you might guess, the syntax for creating a new endpoint is quite complex. Because of this, I am going to focus solely on the syntax required to create a Web service. Listing 1 shows an example of this. We'll walk through each line in detail.

Endpoints are created via the CREATE ENDPOINT statement. This statement consists of four main parts: endpoint name, the initial state, the AS clause, and the FOR clause.

Name and Initial State
The first two parts are easy: they provide a name for the endpoint and specify the state of the endpoint after it is created. The state can be STARTED, STOPPED, or DISABLED. STARTED indicates that the endpoint is actively listening for connections and will respond to connection attempts. STOPPED indicates that the endpoint will listen for connections and will respond to connection attempts, but will refuse the connection and return an error to the client. The last option, DISABLED, indicates that the endpoint will not listen for connections, nor will it respond to connection attempts. STOPPED is the default, but this can be changed either through the CREATE ENDPOINT statement or via an ALTER ENDPOINT statement at a later time.

AS Clause
The AS clause specifies the communications protocol that the endpoint will use. Here we have specified the HTTP protocol, which is the protocol required for a Web service. (TCP is an option for other types of services, and would have different settings than those described here.) The exact implementation details are controlled by a list of specific options included inside parentheses. Those used in our example are described here:

  • PATH specifies the URL of the endpoint. This setting, along with the SITE setting described later, fully specifies the URL that will be used to invoke the Web service. (For example, I've used '/Employee,' so the URL would be HTTP://ServerName/Employee.)
  • AUTHENTICATION specifies the type(s) of authentication that will be used. This is a comma-separated list of authentication methods, including those that we should all be familiar with: BASIC, DIGEST, NTLM, KERBEROS, and INTEGRATED. These work as expected, although additional in-depth information can be found in SQL Server Books Online. My example used Windows Integrated authentication only, so I've specified INTEGRATED.
  • PORTS specifies the type of port to use: CLEAR and/or SSL. CLEAR indicates a non-encrypted port, which requires clients to use the HTTP protocol. SSL indicates an encrypted port, requiring clients to use the HTTPS protocol. If required, both settings can be used simultaneously. The example uses unencrypted HTTP communications, so the appropriate setting is CLEAR.
  • CLEAR_PORT specifies the actual port that will be used by unencrypted communications. If not specified, port 80 is assumed. In this example, I've used port 8080 because my computer has IIS installed, which means that port 80 is already in use. There is also an SSL_PORT setting that we can use if needed, and it defaults to port 443. My example doesn't use SSL, so I haven't included this option.
  • SITE determines the ServerName portion of the Web service URL. If we use an asterisk ("*"), it instructs the endpoint to use all possible host names that aren't explicitly reserved. I used this setting in my example so that both HTTP://localhost/Employee and HTTP://jdixon/Employee would work. If we use a plus sign ("+"), then the endpoint will use all possible host names, even if they are reserved. Finally, we could explicitly specify the host name, which would ensure that only that name would be used.
  • COMPRESSION specifies whether client requests for compressed communications will be honored. If enabled, GZIP encoding will be used when client requests include the appropriate HTTP encoding header. Disabled is the default, and specifies that compression will not be used even if the client properly requests it. I've chosen to enable compression in the example, although I don't specifically need it.
Our example AS clause is now complete. There are other settings that can be used, especially when different authentication methods are chosen, but those are beyond the scope of this article. Instead, we need to move on and set up our service options.

FOR Clause
The FOR clause specifies the service that the endpoint provides. This can be SOAP, SERVICE_BROKER, or DATABASE_MIRRORING. We want to create a Web service, so we must choose SOAP. (Once again, the possible settings vary greatly depending upon which option we choose, so I'm going to restrict my explanation to SOAP-specific settings. Consult Books Online for more details.) The FOR clause consists of one or more WEBMETHOD clauses followed by some service-wide settings.

The WEBMETHOD clause does exactly what you would expect; it defines a single Web method. If a Web service needs multiple methods, then multiple WEBMETHOD clauses will be needed. In our example, there are two methods. The two methods are quite similar; therefore, I'll describe just the first one.

The first part of the WEBMETHOD clause defines the name, or alias, of the method. The alias can also include a namespace, but this is optional. If the namespace is not included, then the namespace from the endpoint is used instead. (The endpoint's namespace will be described in a moment.) After the alias, additional settings are used to specify exactly how this method will function. Note that these settings are included inside parentheses, and that the parentheses are required.

  • NAME specifies the fully-qualified name of the stored procedure or user-defined function that will be invoked by the method. The name must be in the standard database.owner.name format. My example uses a stored procedure named uspGetEmployeeManagers that is found in the AdventureWorks database, within the dbo schema.
  • SCHEMA determines whether the SOAP message for this method will include an inline XSD schema. There are three options; NONE, STANDARD, and DEFAULT. NONE specifies that no schema will be used, while STANDARD specifies that one will. DEFAULT specifies that the setting from the endpoint itself should be used. If no value is specified, DEFAULT will be assumed.
  • FORMAT determines the exact content of the method response. The options are ALL_RESULTS, ROWSETS_ONLY, and NONE. ALL_RESULTS instructs the method to return not only the output from the stored procedure or user-defined function, but also the row count and any error messages or warnings that may exist. ROWSETS_ONLY omits everything but the actual results. NONE suppresses the results too, making this option useful only in very specific circumstances (see SQL Books Online for details). The example uses ROWSETS_ONLY.
In the example, the second WEB-METHOD clause is almost identical to the first, so we'll move on to the service-wide settings.

The final four settings apply to the whole Web service, and not to a specific method:

  • BATCHES specifies whether ad hoc T-SQL statements can be executed via this service. DISABLED, the default, prevents this. ENABLED allows it. When enabled, a special method called SQLBATCH will be created that supports ad hoc queries.
  • WSDL determines the type of WSDL (Web Services Definition Language) document that the Web service will generate. A value of NONE prevents the WSDL from being generated. DEFAULT, on the other hand, directs that the WSDL will be generated. In those rare cases where a special WSDL document is needed, you can specify the name of a stored procedure that returns the special document.
  • DATABASE identifies the name of the database context against which the Web methods will be executed. Our service uses the AdventureWorks database, so that name is included here. If DEFAULT is specified instead, then the default database for the login will be used.
  • NAMESPACE specifies the namespace for the endpoint. If DEFAULT is used, or if no namespace is specified, then the namespace will be HTTP://tempuri.org. If a namespace is included at the WEBMETHOD level, then that namespace will override the one provided here.

More Stories By Jerry Dixon

Jerry Dixon is a senior developer and architect for ACH Food Companies in Memphis, Tennessee. Over the past 16 years he has led development projects for a number of enterprise, mid-level, and small business organizations. While he has fulfilled multiple roles as an infrastructure designer, database administrator, and software developer, he specializes in XML, SQL and ASP.NET. He is a co-leader and frequent presenter at the Memphis .NET User Group. Jerry holds the following Microsoft certifications: MCSD (VB 6.0 and .NET), MCDBA (SQL 2000), MCSA (Windows 2000 and 2003), MCSE (Windows 2000), MCAD (.NET), MCT. He resides in Olive Branch, MS with his wife and son.

Comments (0)

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


@ThingsExpo Stories
Too often with compelling new technologies market participants become overly enamored with that attractiveness of the technology and neglect underlying business drivers. This tendency, what some call the “newest shiny object syndrome,” is understandable given that virtually all of us are heavily engaged in technology. But it is also mistaken. Without concrete business cases driving its deployment, IoT, like many other technologies before it, will fade into obscurity.
The Internet of Things is in the early stages of mainstream deployment but it promises to unlock value and rapidly transform how organizations manage, operationalize, and monetize their assets. IoT is a complex structure of hardware, sensors, applications, analytics and devices that need to be able to communicate geographically and across all functions. Once the data is collected from numerous endpoints, the challenge then becomes converting it into actionable insight.
Consumer IoT applications provide data about the user that just doesn’t exist in traditional PC or mobile web applications. This rich data, or “context,” enables the highly personalized consumer experiences that characterize many consumer IoT apps. This same data is also providing brands with unprecedented insight into how their connected products are being used, while, at the same time, powering highly targeted engagement and marketing opportunities. In his session at @ThingsExpo, Nathan Treloar, President and COO of Bebaio, will explore examples of brands transforming their businesses by t...
With the Apple Watch making its way onto wrists all over the world, it’s only a matter of time before it becomes a staple in the workplace. In fact, Forrester reported that 68 percent of technology and business decision-makers characterize wearables as a top priority for 2015. Recognizing their business value early on, FinancialForce.com was the first to bring ERP to wearables, helping streamline communication across front and back office functions. In his session at @ThingsExpo, Kevin Roberts, GM of Platform at FinancialForce.com, will discuss the value of business applications on wearable ...
With the proliferation of connected devices underpinning new Internet of Things systems, Brandon Schulz, Director of Luxoft IoT – Retail, will be looking at the transformation of the retail customer experience in brick and mortar stores in his session at @ThingsExpo. Questions he will address include: Will beacons drop to the wayside like QR codes, or be a proximity-based profit driver? How will the customer experience change in stores of all types when everything can be instrumented and analyzed? As an area of investment, how might a retail company move towards an innovation methodolo...
The Internet of Things (IoT) is about the digitization of physical assets including sensors, devices, machines, gateways, and the network. It creates possibilities for significant value creation and new revenue generating business models via data democratization and ubiquitous analytics across IoT networks. The explosion of data in all forms in IoT requires a more robust and broader lens in order to enable smarter timely actions and better outcomes. Business operations become the key driver of IoT applications and projects. Business operations, IT, and data scientists need advanced analytics t...
While many app developers are comfortable building apps for the smartphone, there is a whole new world out there. In his session at @ThingsExpo, Narayan Sainaney, Co-founder and CTO of Mojio, will discuss how the business case for connected car apps is growing and, with open platform companies having already done the heavy lifting, there really is no barrier to entry.
Contrary to mainstream media attention, the multiple possibilities of how consumer IoT will transform our everyday lives aren’t the only angle of this headline-gaining trend. There’s a huge opportunity for “industrial IoT” and “Smart Cities” to impact the world in the same capacity – especially during critical situations. For example, a community water dam that needs to release water can leverage embedded critical communications logic to alert the appropriate individuals, on the right device, as soon as they are needed to take action.
SYS-CON Events announced today that HPM Networks will exhibit at the 17th International Cloud Expo®, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. For 20 years, HPM Networks has been integrating technology solutions that solve complex business challenges. HPM Networks has designed solutions for both SMB and enterprise customers throughout the San Francisco Bay Area.
SYS-CON Events announced today that Micron Technology, Inc., a global leader in advanced semiconductor systems, will exhibit at the 17th International Cloud Expo®, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. Micron’s broad portfolio of high-performance memory technologies – including DRAM, NAND and NOR Flash – is the basis for solid state drives, modules, multichip packages and other system solutions. Backed by more than 35 years of technology leadership, Micron's memory solutions enable the world's most innovative computing, consumer,...
As more intelligent IoT applications shift into gear, they’re merging into the ever-increasing traffic flow of the Internet. It won’t be long before we experience bottlenecks, as IoT traffic peaks during rush hours. Organizations that are unprepared will find themselves by the side of the road unable to cross back into the fast lane. As billions of new devices begin to communicate and exchange data – will your infrastructure be scalable enough to handle this new interconnected world?
Through WebRTC, audio and video communications are being embedded more easily than ever into applications, helping carriers, enterprises and independent software vendors deliver greater functionality to their end users. With today’s business world increasingly focused on outcomes, users’ growing calls for ease of use, and businesses craving smarter, tighter integration, what’s the next step in delivering a richer, more immersive experience? That richer, more fully integrated experience comes about through a Communications Platform as a Service which allows for messaging, screen sharing, video...
SYS-CON Events announced today that Pythian, a global IT services company specializing in helping companies leverage disruptive technologies to optimize revenue-generating systems, has been named “Bronze Sponsor” of SYS-CON's 17th Cloud Expo, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. Founded in 1997, Pythian is a global IT services company that helps companies compete by adopting disruptive technologies such as cloud, Big Data, advanced analytics, and DevOps to advance innovation and increase agility. Specializing in designing, imple...
In his session at @ThingsExpo, Lee Williams, a producer of the first smartphones and tablets, will talk about how he is now applying his experience in mobile technology to the design and development of the next generation of Environmental and Sustainability Services at ETwater. He will explain how M2M controllers work through wirelessly connected remote controls; and specifically delve into a retrofit option that reverse-engineers control codes of existing conventional controller systems so they don't have to be replaced and are instantly converted to become smart, connected devices.
SYS-CON Events announced today that IceWarp will exhibit at the 17th International Cloud Expo®, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. IceWarp, the leader of cloud and on-premise messaging, delivers secured email, chat, documents, conferencing and collaboration to today's mobile workforce, all in one unified interface
WebRTC has had a real tough three or four years, and so have those working with it. Only a few short years ago, the development world were excited about WebRTC and proclaiming how awesome it was. You might have played with the technology a couple of years ago, only to find the extra infrastructure requirements were painful to implement and poorly documented. This probably left a bitter taste in your mouth, especially when things went wrong.
As more and more data is generated from a variety of connected devices, the need to get insights from this data and predict future behavior and trends is increasingly essential for businesses. Real-time stream processing is needed in a variety of different industries such as Manufacturing, Oil and Gas, Automobile, Finance, Online Retail, Smart Grids, and Healthcare. Azure Stream Analytics is a fully managed distributed stream computation service that provides low latency, scalable processing of streaming data in the cloud with an enterprise grade SLA. It features built-in integration with Azur...
Akana has announced the availability of the new Akana Healthcare Solution. The API-driven solution helps healthcare organizations accelerate their transition to being secure, digitally interoperable businesses. It leverages the Health Level Seven International Fast Healthcare Interoperability Resources (HL7 FHIR) standard to enable broader business use of medical data. Akana developed the Healthcare Solution in response to healthcare businesses that want to increase electronic, multi-device access to health records while reducing operating costs and complying with government regulations.
For IoT to grow as quickly as analyst firms’ project, a lot is going to fall on developers to quickly bring applications to market. But the lack of a standard development platform threatens to slow growth and make application development more time consuming and costly, much like we’ve seen in the mobile space. In his session at @ThingsExpo, Mike Weiner, Product Manager of the Omega DevCloud with KORE Telematics Inc., discussed the evolving requirements for developers as IoT matures and conducted a live demonstration of how quickly application development can happen when the need to comply wit...
The Internet of Everything (IoE) brings together people, process, data and things to make networked connections more relevant and valuable than ever before – transforming information into knowledge and knowledge into wisdom. IoE creates new capabilities, richer experiences, and unprecedented opportunities to improve business and government operations, decision making and mission support capabilities.