You don’t.
Tableau Desktop will allow you to union multiple tables from the same database or even multiple .csv files, but you can’t union a table from SQL Server A with a tableau from SQL Server B.
Complex data questions are hard to answer with simple visuals. When questions have multiple components, a single graph may not be enough. For instance, imagine you have a table of data displaying average daily high temperatures by month that looks like this:
If you've ever tried to compare part of your data to the whole in Tableau (and give your users flexibility to change the view), you might think it's not possible. However, with a combination of parameters and calculations, you can give users the ability to compare a partial selection to the whole, original value.
Let’s say you want to compare a value from today to the same day last year to evaluate performance…
Creating calculated fields in Tableau Prep is pretty straightforward. Editing them isn’t. The first time I wanted to edit a calculated field in the product I had a moment of hesitation.
Tableau Prep is a powerful tool but it can’t help solve every data preparation scenario. We focus a lot of our time and effort on what it can do, but we thought it would be worthwhile to cover what it can’t do (yet).
Joins can be a sticky business, especially if…
● You haven’t used them much before.
● You are working with data that is new to you.
● You don’t trust your data cleanliness.
Remember the Attribute function? It returns a value if there is only a single value for a result set, otherwise it returns an asterisk.
As you likely know from using Table Calculations in Tableau, they only compute against the marks displayed in a worksheet. Check out this webinar in you need a refresher.
That means when a filter is applied to the worksheet, a table calculation will update to reflect only the data present in the worksheet.
Tableau Prep is a great tool for dealing with messy or unorganized data. After understanding the basics, one of the first things I found myself wondering was “does Tableau Prep have the ability to unpivot data?”. It has a pivot feature but does not have an unpivot or transpose feature at this point. However, there is a workaround.
Spend your time focusing on high-priority tasks, not getting frustrated trying to get Tableau to work. Sign up for a workshop below to learn the skills you need to accomplish your tasks more quickly!
Have you received the error “Cannot mix aggregate and non-aggregate arguments with this function.” in Tableau before?
I have worked with a number of educational institutions, What I’ve found about those institutions, and many other organizations, is that many of them customize the way they track data over time. With a school it might be by trimester, with a restaurant chain it might be by period (there are 13 per year). These types of date fields require customized calculations.