In this lesson, we'll focus on preparing your data for import, and I'll illustrate how to connect to different types of data using Tableau Public. Before connecting to your data, you need to make sure that the data is correctly prepared. If the data is not prepared correctly, it will be very difficult for Tableau to recognize and utilize for analyses. Let me show you what I mean. For Tableau Public, there are three steps to format your data correctly. First, make sure that your data begins in column A1 and that the first row of data only includes column headers. Second, make sure each column of data contains the same type of data throughout the column and each row of data is one data item. Finally, remove any column or row totals. Once your data is correctly formatted, you are ready to import the data into Tableau Public. When you first open Tableau Public, you will be directed to the Tableau Public home page. On the left side of the screen, you will notice that Tableau Public gives you the option to connect to an Excel file, Text file, Access file, or Statistical file located on your PC or Mac, or the option to connect to an OData or Web Data Connector Server. The Excel, Text, Access, and Statistical files will be local databases, such as files located on your own computer, while the OData and Web Data Connector will allow you to connect to an online database. We will discuss first how to connect to one of your local databases and then I will show you how to connect to the OData and Web Data Connector. So let's first connect to your local database or an Excel, Text, Access, or Statistical data file by clicking on the file type. For this example, we will use data that is stored in a Microsoft Excel file. From the open file window, navigate to where the file is stored and click "Open". Tableau Public will import every sheet that resides within the Excel workbook and each sheet will appear under sheets here at the bottom of the worksheet, similar to tab worksheet file management people have come to expect from Excel. Click on the sheet that contains the data you would like to analyze and drag it to the drag sheets here area. You now have a visual representation of your data, and it should look very similar to the original Excel data. As you can see, each column has a header name and the data type is automatically identified by Tableau through the use of icons. An ABC icon represents string data, for example, data that includes names. A globe icon represents geographical data, for example, data that includes cities, states, zip codes, et cetera. A calendar icon represents dates, and the pound icon represents numeric data. If Tableau incorrectly assigned a data type, you can click on the associated icon and choose the correct data type. If everything looks correct, you can click on sheet one and begin analyzing your data. Shifting gears, let's take a look at Tableau's Open Data Protocol Connection. An OData connection defines a protocol for acquiring and updating of data utilizing existing web protocols, such as Microsoft SharePoint server lists. OData is intended to be used to access information from a variety of sources including, but not limited to, relational databases, file systems, content management systems, and traditional websites. If you want more information on OData connections, I have included the link to visit the Microsoft OData within the resources. To make an OData connection, first we click on OData from the Tableau Public home page under servers. From the OData connection window, enter the URL to where the data is located. If no authentication information is necessary, click on "None". If authentication information is needed, enter your account key for Windows Azure Marketplace Data Market or your username and password for the URL you entered. We can click "Okay", and the connection will pull in the available data for you to analyze. For more information on Tableau's OData connection, I have included a link within the resources. Finally, another connection type that Tableau Public provides is a Web Data Connector. A Tableau Web Data Connector gives you a way to connect to data that doesn't already have a connector. Using a Web Data Connector, you can create and use a connection to almost any data type that is accessible over HTTP. This can include Internal Web Services, websites, JSON data, XML data, REST APIs, and many other sources. Because you control how the data is retrieved, you can even combine data from multiple sources. You will need to use the Web Data Connector when you need to connect to any data source that is accessible via JavaScript, but not currently listed in the native tab flow connections. In order to make use of a Web Data Connector, you don't need programming experience whatsoever. If you are aware of a Web Data Connector you want to use, all you need to know is a URL to access that. Simply select the Web Data Connector from the connection list, enter or paste the URL of the Web Data Connector into the appropriate window and follow the instructions presented. The URL of the Web Data Connector may be different from the site that holds your data. If the connector displays a web page, enter any information that you are prompted for and then submit the page. Wait while the connector retrieves your data and imports it into Tableau as an extract. When Tableau opens a new worksheet, you can begin your analysis. Each Web Data Connector is unique and its interface depends on how the author has designed it. For additional information on Tableau's Web Data Connector, please visit the links in the resources. However, if you do not have a Web Data Connector, you will need to create one. This involves programming and knowledge of JavaScript. Additional information on creating a Web Data Connector can be found in the resources. Now that we have our data imported, in the next lesson, we will discuss the two primary types of data connections for Tableau, a live connection and a data extract.
