Microsoft Office Tutorials and References
In Depth Information
What Is Excel Services?
logic. The workbooks then serve as a specification for the developers who recode the logic in a formal
programming language, and incorporate it in the target applications. This process is error-prone and
costly. The developer needs to mimic the Excel model exactly and guarantee the same results. The cost
of recoding and maintaining the code with every change to the workbook are high.
Excel can be called programmatically, but this solution is often not robust enough. This is especially true
when the application calling the model must scale to support many such calculations with high
availability. Excel is designed as a client application and, as such, there are limitations that affect these scenarios.
There is, therefore, a need to support leveraging the business logic defined in Excel workbooks
programmatically as part of scalable applications.
Offloading Spreadsheet Calculations to Servers
Some workbooks take a long time to calculate. Although many workbooks calculate instantaneously,
there are also workbooks that take minutes and even hours to calculate. In some cases, calculating a single
instance of the workbook may be very quick, but you have to repeat the calculation many times with
different inputs. A great example for this is calculating risk using a Monte Carlo simulation. Though
each calculation of the workbook may be short, it could require thousands of iterations with different
input to return the needed results.
There is no doubt that the need to distribute workbooks is applicable to a broader set of users than
dealing with workbooks that take a significant amount of time to calculate. But the cost this issue creates
is significant. When these long-running calculations are taking place, you’re blocked from using your
computer for any additional work. When the calculation takes minutes or even hours, the ramifications
The following section introduces you to Excel Services and how it can help address these needs.
What Is Excel Services?
Excel Services is a new server-side technology that is shipping in Microsoft Office 2007. It is not a
product onto itself, but rather an integrated set of features that is part of the new Microsoft Office SharePoint
Server 2007 (more on this product in the next section).
At its core, Excel Services enables you to calculate workbooks authored in the Excel client on a server,
and distribute the updated results through either a browser-based interface or a programmatic interface
in the form of web services. Excel Services extends the Excel client to the server, and, together with the
rest of Office SharePoint Server functionality, provides an answer to the problems and needs described
With Excel Services, you can broadly distribute workbooks in a secure, controlled, and managed way. You
can guarantee that only the correct version of the workbooks you author are accessed; that the details and
formulas in the workbook are hidden and secure; and that the workbook has gone through the
appropriate approval processes and is managed by the records-management policies of the organization. You can
incorporate workbooks as integral parts of BI dashboards and portals, and offload workbook calculations
from the client to free up desktop machines. And you can use workbook models and their results directly