PowerPivot Microsoft s Answer to Self-Service Reporting

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1 PowerPivot Microsoft s Answer to Self-Service Reporting Microsoft s Latest Foray in the Business Intelligence Arena COLLABORATIVE WHITEPAPER SERIES

2 In the last quarter of 2010, Microsoft first introduced PowerPivot into the Business Intelligence (BI) market with the release of SQL Server 2008 R2. PowerPivot is the latest addition to the Microsoft BI stack and is being touted by Microsoft as the answer to self-service BI. So what exactly is PowerPivot? PowerPivot was initially, at the time of its launch, a free, downloadable add-in (available from Microsoft) to Excel Today, with the latest version of Excel, it is still an add-in but is now integrated in to the core product of both the professional plus version of Excel 2013 and the Office 365 professional plus version. One of the key features of PowerPivot is that it enables an Excel user to bring in millions of rows of data from a variety of different data sources, join them together and then create basic reports and charts in minutes. Virtually everyone has hit limits loading data into Excel. With PowerPivot for Excel, a user can now load over 100 million rows of data very quickly and get back aggregated results such as total revenue, on the fly, without the need for any pre-calculated results. To liken this to other capabilities in the BI marketplace, PowerPivot is an in-memory analytics tool like QlikView. This is PivotTables on Steroids! I. PowerPivot What it is and what it isn t What it is As stated above, PowerPivot is an add-in for Excel. Once installed (with Excel 2010) or activated (with Excel 2013), PowerPivot appears as a menu option on the main Excel ribbon. Clicking this option reveals the main PowerPivot menu as Figure 1 reveals. PowerPivot enables a user to load and join data from a wide variety of sources Relational databases - such as SQL Server, DB2 or Oracle, Analysis Services cubes, Reporting Services files, text files, atom data feeds, or any OLEDB/ODBC data source. One of the key benefits with PowerPivot is that users can combine any of the above data sources with data contained in an Excel Table. Each data source (including an Excel Table) loads into a separate tab. Data can be sorted and filtered on the way into PowerPivot without writing any code or SQL all through a GUI interface! It is important to note that using this GUI approach values that do not exist in the data cannot be filtered out. The data brought in can be augmented by creating new Derived Analysis Expressions (DAX). 2

3 Figure 1: PowerPivot in Excel Most data warehouses or data marts do not contain all the data sources that are needed across the organization and so PowerPivot allows you to easily combine and link your own Excel tables with these other sources a feature that is extremely important to virtually all business analysts. With PowerPivot you can load and filter data on the way into Excel without having to write a lick of SQL, as well as filter data once it s in. Different data sets can only (in this version) be joined via a single column. If multiple columns are needed to perform a join, a compound key could be created within PowerPivot and then this key used for the join. This is illustrated in Figure 2, which shows the popup menu used to create a relationship, known as a join in PowerPivot terminology. Under the hood, PowerPivot creates a virtual Analysis Services cube and uses Vertipaq (a compression technology that Microsoft acquired) to drastically reduce the amount Figure 2: PowerPivot join of space needed to save an Excel file once it s been loaded with data. As the underlying engine is Analysis Services, PowerPivot offers a vast array of date and time intelligence functions and capabilities. With PowerPivot a user has access to functions such as TOTALQTD, TOTALYTD, SAMEPERIODLASTYEAR, NEXTMONTH, NEXTYEAR and ENDOFMONTH. PowerPivot also has special functions to deal with measures that do not aggregate across time such as Inventory. What can be done with the data once it s in Excel? As stated briefly above, new calculated columns of data can be added in PowerPivot by using DAX. At first glance, DAX functions look very similar to existing Excel functions, but the major difference is that functions in Excel normally operate on cells or ranges, whereas DAX functions operate on whole columns, tables and measures, as well as relationally across tables. There are numerous DAX functions that span the following categories: filter, logical, text, aggregate, and date and time intelligence. By default, the outcome of a DAX formula would be based on the filter s (Slicer) settings. For example, if Year was a slicer and 2008 was selected and you had two columns Revenue and % of Total with Products for Rows, the results of the table would show product Revenue and % of Total for 2008 for all products. This can be overridden in cases where you may want to show the % of Total for all years and not just the Year or Years selected. A few brief examples of DAX functions are: 3

4 SUM (Orders [OrderID]) - In this example, Orders is the tab name (based on a table called orders) and [OrderID] is the column name CALCULATE (SUM ( Order Details [Sales Amount]), ALL(Orders)) RIGHT (Orders [OrderID], 2) RELATED (Products [Category]) After data has been brought in, all the necessary columns added, and the joins made, there are several ways to report on data: The main two ways are to create either PivotTables or PivotCharts (an example of the type of reporting that can be created is given at the end of this document). Write an SQL Server Reporting Services report on a PowerPivot model published to SharePoint. Use the GETPIVOTDATA() function from Excel. An example of this type of function would be =GETPIVOTDATA( [Measures].[Sum of Quantity], $A$1, [Products].[Category], [Products]. [Category].&[Beverages] ). organization, you need to use SharePoint 2010 or later (this uses Excel Services and PowerPivot Galleries and Libraries so that non PowerPivot users can view and interact with the analysis without having PowerPivot on their desktops). It should be noted that if a PowerPivot model is created using Excel 2013, it cannot be shared to someone using an earlier (Excel 2010) version. Most organizations even if they are Microsoft centric are normally slow to adopt the latest release (2013) of Office and so will make the roll out and adoption of this technology (other than on isolated PC s) slower in the market. Another important distinction is whether a user has a 32 or 64 bit operating system (OS). Having a 64 bit OS allows a user to load in more rows and have faster aggregations. In tests on a normal laptop using the 32 bit PowerPivot version (in Excel 2010), 3.7 million rows of data were loaded in approximately five minutes. PowerPivot had no problems with all totals appearing instantaneously. Figure 3: Value fields Use Excel s CUBE functions. An example of this type of function would be =CUBEMEMBER( PowerPivot Data, [Measures].[Sales], Sales ). Use a third party tool such as Tableau. Fortunately for the user, both the GETPIVOTDATA and CUBEMEMBER functions are self-generating once a user types the = sign in a cell. Saving a PowerPivot analysis is just like saving an Excel file and on the face of it seems like just an ordinary Excel file, but by changing the extension to be.zip instead of.xlsx, the difference becomes clear. If you open this file with a viewer like WinZip, you will see that in fact there are several folders, and by exploring one of them xl, CustomData you will see the size of the compressed data file. The term free was used earlier, but there is a hidden cost to PowerPivot. First, you either need to upgrade to Excel 2010 or Excel 2013, and secondly, in order to share any information created using PowerPivot around the 4

5 Even outside of PowerPivot, Excel 2010 and later has some interesting PivotTable features such as slicers (filters) that allow a user to easily filter data. Slicers can be used when creating any PowerPivot Analysis to enable a user to very easily filter the data that they need. Another PivotTable feature that is extremely useful, and again worthy of note, enables the user to select a value field such as Revenue, place this in the data area, and then drag the field again into the data area and convert it to a variety of formats such as % of Total or Rank. This feature can create a multitude of typical calculations used in reporting in a few simple mouse clicks, whereas in other BI tools this involves creation of formulas and utilizing various functions within the various tools no easy task. This feature is illustrated in Figure 4. In this example, Internet Sales Amount was dragged into the data area twice. By right clicking and selecting Show Values As, a sub menu showing all the different options appears. By selecting % of Column Total the values appear as follows, automatically formatted. This new column can easily be renamed to a more appropriate name. What it isn t What are the gaps or cons of using PowerPivot? One of the most important elements missing from this tool is a robust Figure 4: Selecting value fields semantic layer that can be shared across the organization and security. A semantic layer is one element that many BI tools provide (for example in BusinessObjects, this layer is called a Universe, and in Cognos, it is called Framework Manager Model) that shields a user from the joins and underlying table structures. Another gap lies within the security capabilities of PowerPivot. The only security offered is by either SharePoint or the user account for the underlying database access. Since its launch, Microsoft has partially addressed the security issue and the semantic layer issue by allowing a PowerPivot model to be deployed to a Tabular Analysis Services model on a server. This model can then have: Role-based security model using Active Directory Row and column level security to secure data at the deepest level Without SharePoint 2010 and beyond, the sharing of analyses created using PowerPivot are going to be limited to those who have PowerPivot installed on their local machines. Another area worth mentioning, where caution should be taken, is the use of date and time intelligence functions. Some functions will only return correct or intuitive results if the dates are contiguous. To get around this issue, the creation of a separate date or time dimension with continuous dates is recommended. II. Summary Most business people conduct reporting in Excel and it is especially important to those in the finance function. When Collaborative Consulting s professionals introduce a new BI tool to a client, one of the most frequently asked questions is can I export that to Excel? The main reasons this may not yet be possible are: The organization may not have a data warehouse, and therefore the data needed for reporting is contained in numerous places. 5

6 The organization has a data warehouse, but the warehouse does not contain all sources necessary for all reporting. The reporting tools typically offered by BI vendors allow for simple report generation, but typically, more complex reports are needed by the business and therefore require more of an IT developer s skill set where things like year over year percent variance calculations are required. For these reasons, many business analysts use tools like Excel and Access to load, manipulate and report on data from multiple sources. Historically, Access has been chosen over Excel because of initial row limits or memory limits with Excel. Access also has a limit on the size of the database it can handle. With PowerPivot, a user has the ability to load massive amounts of data over 100 million rows into Excel and do their reporting, thus enabling business users to do their jobs with greater ease and self-sufficiency. Even though some entire data warehouses could now be loaded into Excel, there will always be a need for a data warehouse. Warehouses typically automate, standardize and cleanse data as well as capture certain attributes so that changes over time can be captured and reported correctly, for example capturing sales force changes and organizational hierarchies. These types of things are much harder to do in PowerPivot. PowerPivot empowers a user with the ability to combine this with other local data to complete reporting without concern for size or row limits. Most BI vendors, and especially those in the in-memory analytics category such as QlikView, will view Microsoft as a threat. The only thing that will slow down adoption in the market is the fact that Office and SharePoint 2010 (or later) will be necessary in order for users to be able to share analysis (although it should be noted that only Office 2010 or later is needed for standalone reporting). The latest version of Excel 2013 with all the new features such as Quick Analysis, Power Maps (allowing excellent geospatial analysis), Power Query and built in office apps to make everyday tasks in Excel even easier, make Excel a formidable self-service tool. Figure 5: An example of the reporting that can be created in Excel. All of Excel s features can be applied and numerous chart types and templates are available. 6

7 Collaborative Consulting is a leading information technology services firm dedicated to helping our clients achieve business advantage through the use of strategy and technology. We deliver a comprehensive set of solutions across multiple industries, with a focus on business process and program management, information management, software solutions, and software performance and quality. We also have a set of offerings specific to the life sciences and financial services industries. Our unique model offers both onsite management and IT consulting as well as U.S.-based remote solution delivery. To learn more about Collaborative, please visit our website at us at sales@collaborative.com, or contact us at Copyright 2014 Collaborative Consulting, LLC. All rights reserved. This product is protected by U.S. and international copyright and intellectual property laws. WP