Event reporting: new report to view the second dimension as columns (Pivot by second dimension)

[mattab]

The goal of this ticket is to provide an alternative display of Event reporting data. Instead of displaying second dimension values in the sub-table, we would to display second dimensions as columns of the report. This is a different view of the existing Event data, which is much more useful data visualisation in many cases.

Context

Event Tracking is a powerful feature of Piwik, letting you track custom events defined by

• Event category,
• Event action,
• Event name (optional),
• Event value (value).

The Event tracking UI displays top Event categories. A click on a given Event category loads top Event actions for this category, or top Event names for this category.

Example

If you track following events (structure { Category, Action, Name }) { Documentary, Watch, Inside Job }, { Documentary, Watch, Thrive }, { Documentary, Download, Zeitgeist }, { Documentary, Buy, Food inc. }

Then you will be able to access a report such as:

Event name	Watch	Download	Buy
Inside Job	111	51	5
Thrive	99	170	17
Zeitgeist	56	40	5
Food inc.	15	32	3

(Watch, Download and Buy are Event Actions.)

Specs

• The rows are not clickable to show sub-tables (since we cannot display the third dimension - it is not archived)
• If there are dozens of actions then the table will get very very wide (dozens of columns).
• The metric displayed in the column is the Total events
• On hover on the metric, we could display a useful tooltip eg. The total Event value is $totalValue. It is the sum of $total events values <br /> between minimum of $minValue and maximum of $maxValue.<br/>Average Event value is: $avgValue
  • make this tooltip text the text for the tooltip on event value as well (reuse the filter)
• Open question: could this feature be somehow generalised to all reports with a sub-table?
  • This feature is a bit similar to Google Analytics "Pivot by [DIMENSION]" (except it's simpler since GA allows Pivot by many dimensions)
• How to order columns? Display columns in descending order of their value, for the value of the first row.
  • Maybe we can also pre-pend the column name with a numeric index like GA does, eg.

Event name	1. Watch	2. Download	3. Buy
Inside Job	111	51	5

Tasks

• Make this available via the API (eg. via a new parameter 'pivotBySecondDimension=1')
• Add a new way in the UI to enable this feature (eg. link 'Pivot by second dimension')
• Add tests
• Update Event Tracking user guide

[quba]

Would it be possible to add also total number of specific actions for whole category? So basically the same visualization, but with event category instead of event name.

[mattab]

Yes definitely, it will be available for all sub-dimensions combinations, so you will be able to see event actions as columns for each event category.

[quba]

What about the column with total number of events? I think it was included in the initial specification.

[mattab]

What about the column with total number of events? I think it was included in the initial specification.

The proposal is to show 9 columns and the 10th. column will contain the sum of values of remaining columns. ie 10. Others aggregate column