Tableau Shows Better Way To Analyze Data

To make data analysis easy for anyone, Tableau Software, recently released VizQL, a breakthrough business intelligence technology that can visually represent data from RDBMS and OLAP servers using a simple, visual front-end. VizQL also refers to Tableau's proprietary language that combines data with visual effects. The product is a result of a five-year research project that took place under the guidance of Stanford University's co-founders of Pixar Animation Studios.

Tableau is a desktop application that installs like any Windows-based program. Once started, users connect to a data source. Using sales data from a large coffee retail operation, engineers were able to test VizQL with data from a sample spreadsheet containing information about various coffee drinks.

Tableau translates data and field names into dimensions and measures. Since dimensions are basically non-numeric category information, Tableau can identify these fields quite easily. Measures, however, can be ambiguous. The software automatically defines fields that contain at least one number as measures. If this is done in error, users simply right-click on the field to change the designation. After initially scanning the spreadsheet for data, CRN Test Center engineers found that Tableau identified all measures correctly and created a cost, inventory and marketing measure that corresponded to columns in the test spreadsheet. In the same pane, Tableau has a workspace where users can query data sources using drag-and-drop technology, ask questions and get answers visually.

Each component in Tableau's canvas is called a shelf. Shelves are boxes where users can drag and drop multiple fields and then stack them to produce a visual output. Tableau provides a shelf for Column, Row, Filter and Level of Detail. For example, Test Center engineers dragged the Market field to the row shelf, and the software immediately queried the test spreadsheet. The software then provided the correct values for all markets in the spreadsheet. Because the data used in the test spreadsheet came from an OLAP cube or a combination of multiple tables, the market column was in a denormalized state. However, Tableau was able to automatically normalize all the fields and provide correct values for each dimension.

By dropping the sales measure with the market dimension, the software summarized all the sales values for each market in a table format. This operation is equivalent to a creating a pivot table or a grid in Microsoft Excel. By continuing to drop other fields—like product type, products and dates—into their respective columns, users can manipulate Tableau to adjust its output table to show drilled-down information. Tableau also allows users to change field views to show dates by month or day, so data can be broken down by time period. CRNTest Center engineers also found that Tableau creates a more efficient method of creating cross-tab analysis tables than other business intelligence tools.

To test the software's visual output, Test Center engineers dragged and dropped the profit measure into the Color shelf. Tableau quickly converted the table view into a two-dimensional bar graph, allowing users to easily identify the best- and worst-selling products in every market. By placing the mouse pointer over any bar, users can view a dialog box indicating the values associated with each product.

To find out how various costs impacted profits, engineers dropped other fields—like marketing—to observe relationships. To drill down into the data, engineers dropped dates into the Level of Detail shelf, and all the data points arranged themselves into market quarters by costs and by markets for each product. To distinguish sales by product, engineers dragged and dropped the product type into the Shape shelf and the software automatically represented each product in the diagram by different shapes. The software provides a legend at the bottom of the canvas for each visual aspect of a diagram and value in each each field measured. Color gradients in the legend show profit or loss as well as numerical ranges on a color scale.

CRN Test Center engineers were very impressed with Tableau's capabilities and were pleased to find that Tableau Software is developing a channel program. Currently, the software is available directly from the vendor. Technical support is offered via the Web or by phone during normal business hours. Tableau Software's Professional Edition is priced at $1,799.