Click here to close now.



Welcome!

Microservices Expo Authors: Jason Bloomberg, Elizabeth White, Anders Wallgren, Pat Romanski, Cloud Best Practices Network

Related Topics: Industrial IoT

Industrial IoT: Article

Integrating Enterprise Information on Demand with XQuery - Part 2

Integrating Enterprise Information on Demand with XQuery - Part 2

In Part I of this article (XML-J, Vol. 4, issue 6), we introduced the enterprise information integration (EII) problem and explained how the XML query language XQuery and related technologies - specifically XML, XML Schema, and Web services - are central to enabling this age-old problem to be successfully addressed at last.

We provided a technical overview of the XQuery language and presented a simple "single view of Customer" example to illustrate XQuery's role in the EII domain. The example was based on an electronics retailer that wanted to share customer information across three portals - portals for customer self-service, credit approval, and product service. The information to be integrated resided in a variety of back-end information sources, including two relational database management systems, an SAP system, and a Web service.

In this article, our XQuery/EII saga continues. In this installment, we look at how EII relates to two other technologies designed for integration tasks, namely enterprise application integration (EAI) and extract-transform-load (ETL) tools. We also take a brief look at BEA Liquid Data for WebLogic, an XQuery-based EII offering, and discuss how XQuery and Liquid Data were put to use recently in a telecommunications-related customer project.

What About EAI?
Given the industry buzz around EAI today, a natural question about EII is "so why bother?" That is, why isn't a modern EAI solution alone - for example, a workflow engine with XML-based data transformation capabilities - sufficient to solve the EII problem? The answer is, in principle, that EAI is in fact sufficient to solve the EII problem. A developer could always choose to hand-build a set of workflows, writing one workflow per application-level "query" to deliver the desired information back to the calling applications. In the example from Part I of this article, three hand-tailored workflows could instead be written to provide information retrieval capabilities comparable to our XQuery-based solution. But is that the best approach, in terms of development time and maintenance cost?

The basic question here is when to use a declarative query language (XQuery in the case of modern EII) versus constructing code in a procedural language (a workflow language in the case of EAI). The lessons from the relational database revolution are clear: When applicable, a declarative approach offers significant advantages. Instead of hand-constructing a "query plan" (EAI workflow) to extract the needed data from each of the data sources in some manually predefined order, the EII approach allows a single, smaller, and simpler declarative query to be written.

The resulting benefits should be obvious. First, the user does not need to build each query plan by hand, which could involve a considerable effort. Instead, the user specifies (when defining the core view) what data sources are relevant and what logical conditions relate and characterize the data to be retrieved. Second, queries can be optimized automatically by the EII middleware, resulting in an optimal query execution plan (order of accessing the sources, queries or methods to extract the data, etc.) for each different query. For example, using EAI, one central workflow could be written to retrieve all of the customer information in Part I's example, and then other workflows could be written to first call this workflow and then further filter the results. However, in the EII approach, the query processor will (for each query) prune out irrelevant data sources as well as push SQL selection conditions (such as only retrieving "Open" support cases in Listing 2 of Part I) down to any RDBMS data sources. Third, as the data sources change over time in terms of their schemas, statistics, or performance, the EII user will not be forced to rewrite all of his or her queries. Simply maintaining each base view query and re-optimizing the other queries will adapt their query execution plans to the new situation. In contrast, in the case of EAI, many workflows would have to be rewritten to handle most such changes.

There really isn't an either/or choice to be made between EAI and EII at all. Both technologies have critical roles to play in an overall enterprise integration solution. These technologies are complementary: EII provides ease of data integration, while EAI provides ease of process integration. EII is appropriate for composing integrated views and queries over enterprise data. EAI is the appropriate technology for creating composite applications that orchestrate the functional capabilities of a set of related but independent applications, Web services, etc. Moreover, EII can be used to handily augment EAI in scenarios where workflows need to access integrated data views. For example, if our electronics retailer wanted its order process to offer free shipping to customers who have ordered more than $1,000 of goods during the year and who have accumulated more than 5,000 reward points, the integrated view of customer from Part I could be used to easily access the relevant information from within the order entry workflow.

What About ETL?
Another technology related to EII is ETL. In fact, ETL tools are designed precisely for the purpose of integrating data from multiple sources. These tools are therefore another category of software that naturally leads to a "why bother with EII?" question - why isn't ETL technology the answer? As you'll see, the answer is again that both technologies have their place in modern IT architectures.

ETL tools are designed for use in moving data from a variety of sources into a data warehouse for offline analysis and reporting purposes. As the name suggests, ETL tools provide facilities for extracting data from a source; transforming that data into a more suitable form for inclusion in the data warehouse, possibly cleansing it in the process; and then loading the transformed data into the warehouse's database. Typical ETL tools are therefore focused on supporting the design and administration of data migration, cleansing, and transformation processes. These are often batch processes that occur on a daily or weekly basis.

Data warehouses and the ETL tools that feed them are invaluable for enabling businesses to aggregate and analyze historical information. For example, our electronics retailer might very well want to keep track of customer data, sales data, and product issue data over a period of years in order to analyze customer behavior by geographic region over time, improve their credit card risk model, and so on. A data warehouse is the appropriate place to retain such data and run large analytical queries against it, and ETL technology is the right technology today for creating, cleaning, and maintaining the data in the warehouse. However, ETL is not the right technology for building applications that need access to current operational data - it doesn't support the declarative creation of views or real-time access to operational data through queries.

For applications that need to integrate current information, Part I of this article showed how XQuery can be used to declaratively specify reusable views that aggregate data from multiple operational stores and how XQuery can be used to write XML queries over such integrated views. We also explained how standard database query processing techniques, including view expansion, predicate pushdown, and distributed query optimization, can be applied to XQuery, making XQuery-based EII an excellent technological fit for such applications.

Clearly, both ETL and EII technologies have important roles to play in today's enterprise. ETL serves to feed data warehouses, while EII is an enabler for applications that need timely access to current, integrated information from a variety of operational enterprise data sources. As with EAI, there are also cases where the two technologies come together. As one example, an ETL tool could be used to help create and maintain a cross-reference table to relate different notions of "customer id" for use in creating XQuery-based EII views across different back-end systems. As another example, an ETL-fed data warehouse could be used to build a portal for analyzing the historical behavior of a company's top customers, with an EII tool used to allow click-through inspection of the customers' purchases in the past 24 hours.

Putting XQuery-Based EII to Work
For the reasons discussed in this article, XQuery-based EII middleware is an emerging product segment that promises to deliver the tools and technology needed in this important space. One commercially available XQuery-based middleware product is BEA Liquid Data for WebLogic. Liquid Data is capable of accessing data from relational database management systems, Web services, packaged applications (through J2EE CA adapters and application views), XML files, XML messages, and, through a custom function mechanism, most any other data source as well. For illustration purposes, the architecture of Liquid Data is depicted in Figure 1. Liquid Data provides default XML views of all of its data sources and provides an XQuery-based graphical view and query editor for use in integrating and enhancing information drawn from one or more data sources. It includes a distributed query processing engine as well as providing advanced features such as support for query result caching and both data-source-level and stored query-level access control.

As a final example of the applicability of XQuery to enterprise information integration problems, we'll describe an actual customer integration exercise where Liquid Data was put to use. In that project, a large telecommunications vendor wanted to create a single view of order information for one of its business divisions. The goal of the project was to make integrated order information available to the division's customers (other businesses) through a Web portal, enabling their customers to log in and check on the status of their orders, as well as making information available to the division's own customer service representatives.

The division had data distributed across multiple systems, including a relational database containing order summary information and two different order management systems. Order details were kept in one or the other of the two order management systems, depending on the type of order. Functionality-wise, a limited view of order details was provided through the customer order status portal that the division built using Liquid Data, whereas customer service representatives were permitted to see all of the order data through their portal. In both cases, it was possible to search for order information by various combinations of purchase order number, date range, and order.

The use of XQuery-based EII technology enabled the customer to complete their portal project in much less time than they had expected it to take with traditional technologies, and their total cost of ownership was also lower due to the reusability of Liquid Data assets and the low cost of maintenance enabled by EII.

Summary
In this article, we have explained how XQuery is beginning to transform the integration world, making it possible to finally tackle the enterprise information integration problem where past attempts have failed. In Part I we provided an overview of XQuery and illustrated how it could be used to integrate the disparate information sources of a hypothetical electronics retailer. In Part II we discussed the relationship of EII to EAI and ETL technologies and then briefly presented BEA's XQuery-based EII product and described one of the customer projects in which it was used.

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.


@MicroservicesExpo Stories
If we look at slow, traditional IT and jump to the conclusion that just because we found its issues intractable before, that necessarily means we will again, then it’s time for a rethink. As a matter of fact, the world of IT has changed over the last ten years or so. We’ve been experiencing unprecedented innovation across the board – innovation in technology as well as in how people organize and accomplish tasks. Let’s take a look at three differences between today’s modern, digital context...
The battle over bimodal IT is heating up. Now that there’s a reasonably broad consensus that Gartner’s advice about bimodal IT is deeply flawed – consensus everywhere except perhaps at Gartner – various ideas are springing up to fill the void. The bimodal problem, of course, is well understood. ‘Traditional’ or ‘slow’ IT uses hidebound, laborious processes that would only get in the way of ‘fast’ or ‘agile’ digital efforts. The result: incoherent IT strategies and shadow IT struggles that lead ...
SYS-CON Events announced today that Commvault, a global leader in enterprise data protection and information management, has been named “Bronze Sponsor” of SYS-CON's 18th International Cloud Expo, which will take place on June 7–9, 2016, at the Javits Center in New York City, NY, and the 19th International Cloud Expo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. Commvault is a leading provider of data protection and information management...
As software organizations continue to invest in achieving Continuous Delivery (CD) of their applications, we see increased interest in microservices architectures, which–on the face of it–seem like a natural fit for enabling CD. In microservices (or its predecessor, “SOA”), the business functionality is decomposed into a set of independent, self-contained services that communicate with each other via an API. Each of the services has their own application release cycle, and are developed and depl...
SYS-CON Events announced today that Alert Logic, Inc., the leading provider of Security-as-a-Service solutions for the cloud, will exhibit at SYS-CON's 18th International Cloud Expo®, which will take place on June 7-9, 2016, at the Javits Center in New York City, NY. Alert Logic, Inc., provides Security-as-a-Service for on-premises, cloud, and hybrid infrastructures, delivering deep security insight and continuous protection for customers at a lower cost than traditional security solutions. Ful...
At the heart of the Cloud Native model is a microservices application architecture, and applying this to a telco SDN scenario offers enormous opportunity for product innovation and competitive advantage. For example in the ETSI NFV Ecosystem white paper they describe one of the product markets that SDN might address to be the Home sector. Vendors like Alcatel market SDN-based solutions for the home market, offering Home Gateways – A virtual residential gateway (vRGW) where service provider...
SYS-CON Events announced today that VAI, a leading ERP software provider, will exhibit at SYS-CON's 18th International Cloud Expo®, which will take place on June 7-9, 2016, at the Javits Center in New York City, NY. VAI (Vormittag Associates, Inc.) is a leading independent mid-market ERP software developer renowned for its flexible solutions and ability to automate critical business functions for the distribution, manufacturing, specialty retail and service sectors. An IBM Premier Business Part...
SYS-CON Events announced today that Catchpoint Systems, Inc., a provider of innovative web and infrastructure monitoring solutions, has been named “Silver Sponsor” of SYS-CON's DevOps Summit at 18th Cloud Expo New York, which will take place June 7-9, 2016, at the Javits Center in New York City, NY. Catchpoint is a leading Digital Performance Analytics company that provides unparalleled insight into customer-critical services to help consistently deliver an amazing customer experience. Designed...
SYS-CON Events announced today that AppNeta, the leader in performance insight for business-critical web applications, will exhibit and present at SYS-CON's @DevOpsSummit at Cloud Expo New York, which will take place on June 7-9, 2016, at the Javits Center in New York City, NY. AppNeta is the only application performance monitoring (APM) company to provide solutions for all applications – applications you develop internally, business-critical SaaS applications you use and the networks that deli...
In the Bimodal model we find two areas of IT - the traditional kind where the main concern is keeping the lights on and the IT focusing on agility and speed, where everything needs to be faster. Today companies are investing in new technologies and processes to emulate their most agile competitors. Gone are the days of waterfall development and releases only every few months. Today's IT and the business it powers demands performance akin to a supercar - everything needs to be faster, every sc...
The (re?)emergence of Microservices was especially prominent in this week’s news. What are they good for? do they make sense for your application? should you take the plunge? and what do Microservices mean for your DevOps and Continuous Delivery efforts? Continue reading for more on Microservices, containers, DevOps culture, and more top news from the past week. As always, stay tuned to all the news coming from@ElectricCloud on DevOps and Continuous Delivery throughout the week and retweet/favo...
In most cases, it is convenient to have some human interaction with a web (micro-)service, no matter how small it is. A traditional approach would be to create an HTTP interface, where user requests will be dispatched and HTML/CSS pages must be served. This approach is indeed very traditional for a web site, but not really convenient for a web service, which is not intended to be good looking, 24x7 up and running and UX-optimized. Instead, talking to a web service in a chat-bot mode would be muc...
More and more companies are looking to microservices as an architectural pattern for breaking apart applications into more manageable pieces so that agile teams can deliver new features quicker and more effectively. What this pattern has done more than anything to date is spark organizational transformations, setting the foundation for future application development. In practice, however, there are a number of considerations to make that go beyond simply “build, ship, and run,” which changes ho...
SYS-CON Events announced today that Interoute, owner-operator of one of Europe's largest networks and a global cloud services platform, has been named “Bronze Sponsor” of SYS-CON's 18th Cloud Expo, which will take place on June 7-9, 2015 at the Javits Center in New York, New York. Interoute is the owner-operator of one of Europe's largest networks and a global cloud services platform which encompasses 12 data centers, 14 virtual data centers and 31 colocation centers, with connections to 195 ad...
With microservices, SOA and distributed architectures becoming more popular, it is becoming increasingly harder to keep track of where time is spent in a distributed application when trying to diagnose performance problems. Distributed tracing systems attempt to address this problem by following application requests across service boundaries, persisting metadata along the way that provide context for fine-grained performance monitoring.
Web performance issues and advances have been gaining a stronger presence in the headlines as people are becoming more aware of its impact on virtually every business, and 2015 was no exception. We saw a myriad of major outages this year hit some of the biggest corporations, as well as some technology integrations and other news that we IT Ops aficionados find very exciting. This past year has offered several opportunities for growth and evolution in the performance realm — even the worst failu...
Are you someone who knows that the number one rule in DevOps is “Don’t Panic”? Especially when it comes to making Continuous Delivery changes inside your organization? Are you someone that theorizes that if anyone implements real automation changes, the solution will instantly become antiquated and be replaced by something even more bizarre and inexplicable?
Welcome to the first top DevOps news roundup of 2016! At the end of last year, we saw some great predictions for 2016. While we’re excited to kick off the new year, this week’s top posts reminded us to take a second to slow down and really understand the current state of affairs. For example, do you actually know what microservices are – or aren’t? What about DevOps? Does the emphasis still fall mostly on the development side? This week’s top news definitely got the wheels turning and just migh...
Test automation is arguably the most important innovation to the process of QA testing in software development. The ability to automate regression testing and other repetitive test cases can significantly reduce the overall production time for even the most complex solutions. As software continues to be developed for new platforms – including mobile devices and the diverse array of endpoints that will be created during the rise of the Internet of Things - automation integration will have a huge ...
Providing a full-duplex communication channel over a single TCP connection, WebSocket is the most efficient protocol for real-time responses over the web. If you’re utilizing WebSocket technology, performance testing will boil down to simulating the bi-directional nature of your application. Introduced with HTML5, the WebSocket protocol allows for more interaction between a browser and website, facilitating real-time applications and live content. WebSocket technology creates a persistent conne...