By far and away the most popular session of the day. Standing room only left over a dozen people with no seat. Pretty amazing for the last session of the day and all in the interest of “time.”
Time is an important part of analysis. Things are constantly changing and our data can tell us that. If data is not constrained by time, it’s meaningless. Tableau has a number of filter options for managing the time dimension.
Using demo stock market data Chuck Hooper, Senior Professional Services Consultant for Tableau, he dragged the IBM stock price onto the screen and then added the date dimension. By default, Tableau displays at the highest level, which in this case was ‘year’ but you can easily drill down to quarter, month and day.
Let the coolness begin. Chuck showed us how to change the typical date display to display only certain days or months, fiscal year start dates, date ranges, and other options. Next he added a trend line with just one click. Right-clicking you get all the technical logic (metadata) behind it so you can impress your friends. He warned us to be careful that it is very easy to create a trend line to show what you want the data to be but might not be an honest representation.
Next he talked about relative dates. That means ‘relative to now’, which is actually what the menu option is called. That includes things like last 3 months, prior year, quarter to date, etc.
Now we’re really rolling. Time for calculated dates. This option lets you format or convert data into a date, identify the “first” of anything (year, quarter, month, week number, day of year), and create combinations of dates like today plus the same day last month.
Lastly, Chuck demonstrated additional ways to add context including how to add annotations to the data which stays with the data even if you filter them and reference lines. He wrapped up his presentation by creating a dashboard that uses on chart as a filter to another chart. Change data in the master chart and the linked charts change with it. Cool!