Event Custom Variable Key/Value

[Optizent]

What are Event Custom Variable Key/Value? I can’t find any documentation on it?

[Oliwer_Kaczmarek]

Hi Anil,

Event (and Session) Custom Variables Key/Value, are similar feature to what custom dimensions are, but in case of custom variables, when sending them to Piwik PRO you also specify the key.
Let’s say you want to send information about someone’s gender. You could create a new custom session dimension called “gender” and send data to it with a page view, custom event, ping or whatever other event you would like to use for that.
But you could also use custom variables. In that case, you do not create any new custom variable in the UI, you simply send an event with additional session custom variable key: “gender”, and the session custom variable value: [visitor’s gender].

Custom variables are more flexible in regards to tracking compared to custom dimensions, but are also slightly harder to use in analytics (as they do not show you the key value like “gender” but will display “event custom variable key 1” for example, so you have to remember what did you use it for). Also you can use only up to 5 custom variables for session scope and 5 for event scope in a single event (6-10 are reserved for in tool needs, but they are still visible in the UI), while for custom dimensions you have 200 for event scope and 200 for session scope that you can add to a single event.

Here’s documentation on implementing it: setCustomVariable

Best,
Oliwer