by Chris Pragash

Anyone familiar with the SharePoint world is sure to have heard about the term Business Data Catalog or BDC. The concept was introduced in SharePoint 2007 and was touted as one of most powerful new additions. Marketing personnel would use the keyword BDC as one of their main selling points of SharePoint 2007. Some other terms used along with BDC included keywords like “No code solutions” and “Out of the box solutions.” Sometimes it made me wonder what “out of the box” really meant; did that mean included in the “box” or NOT included in the “box?” Both ways, the statement “out of the box” made sense!

Once the mud settled on what BDC meant, how it worked, its limitations, and the cost, there was some amount of skepticism about its potential. Although the “No code solutions” marketing pitch was true, it came with its own limitations. Technically, the functionality provided by BDC was always possible through custom solutions; hence, there was always a debate between .NET architects and SharePoint architects on the pros and cons of using the BDC.

Although BDC in SharePoint 2007 itself provided good benefits, there were some major limitations—from a technical as well as cost perspective. The toolset that was available from Microsoft to define and configure BDC was not comprehensive. Third-party tools were required to utilize the full capabilities of the feature. Another main drawback for BDC was its cost; it was only available with SharePoint Enterprise Edition, and it required some investment in terms of resources to get it working. A pure technical limitation of the BDC was that it did not provide any CRUD (read/write) operations; it only provided a read-only view of the data.

What Is BCS and Why Should We Consider It?

Business Connectivity Services (BCS) is the next-generation evolution of BDC. You may still hear the term BDC in SharePoint 2010, but in the new world, BDC stands for Business Data Connectivity, which is essentially the connection portion of the BCS suite of components. BDC in SharePoint 2010 is actually the BDC from SharePoint 2007.

The main purpose of this feature is still very much the same as its predecessor—to connect with external data sources from within SharePoint. However, BCS extends that capability beyond just SharePoint and makes it available to other clients such as Microsoft Office. In other words, BCS is a set of components that includes connectors to different data sources and a runtime engine that uses connectors to connect to the data sources.

BCS attempts to overcome its predecessor’s limitations with a new set of integrated tools (the new SharePoint 2010 designer and Visual Study 2010) and a powerful and extensible platform that provides full CRUD operations. Another major advantage of BCS is that it is built-in to SharePoint 2010 Foundation, which is the next generation of Windows SharePoint Services. I am expecting the next round of new keywords from solution marketers to be “It’s Free!!,” which is actually true and the free no-code solution can accomplish quite a lot in the new SharePoint world. I will explore this idea in more detail in the upcoming sections.

BCS Building Blocks

Now that I have provided my own marketing spiel on BCS, let’s discuss more about why the new BCS is worth considering. To start, let’s take a high-level view of the main building blocks. Figure 1 shows a high-level block diagram of BCS and its components.

Figure 1: The three layers of the BCS architecture. This diagram presents three layers of the BCS architecture:

1. Presentation Layer: This layer includes tools that allow users to work with the data presented by the BCS components. Within SharePoint, presentation components include a new type of list called “external lists,” out-of-the-box Web parts (yes, it is included with SharePoint, but Enterprise Edition only) and from within search (Standard and Enterprise Editions only).
2. Runtime Layer: This layer is the meat of the entire BCS architecture. This layer has three main components:
   1. External Content Type (ECT): Contains the metadata definitions of the external content, connection details and details about the actions such as read/write operations, performed on the external content. For example, if you consider a custom database with say, sales and customer information, an ECT for the customer information will include the data column definition such as Customer Name, Address, and ID as well as the connection details to the database and details of how perform the read/write/update/delete operations.
   2. Runtime: This is the main engine that performs operations between the client tools and the content source. The BDC runtime is built-in to office clients such as Word, SharePoint workspace, Access, and InfoPath, and within SharePoint 2010 itself. As the runtime is built-in to the office clients, these tools can work with the data sources directly and do not need SharePoint as the intermediary layer.
   3. Connectors: The connectors provide, well, the connectivity, to the specific content source. SharePoint 2010 has three connectors out of the box: a SQL connector, a WCF connector, and a .NET assembly connector. Besides the default set of connectors, the framework is extensible, which means custom connectors could be built for specific content sources.
3. Content Sources: This layer is kind of self explanatory! Contains the data sources.

Read more about SharePoint 2010 Business Connectivity Services in the next tip entitled SharePoint 2010 Business Connectivity Services – High-Level Walkthrough.

About the Author

Chris Pragash has more than 12 years of experience in the IT industry. His primary focus has been architecting and developing solutions based on Microsoft platforms. He started working on SharePoint in its 2003 version and has designed and developed various types of solutions, including corporate intranets, company Internet Web sites, BI dashboards, and publishing Web sites. His academic background includes PMP, MS Project Management, MCSD (.NET), and MCP (SharePoint 2007 administration). He is currently working on his MBA in strategic management.