Google Analytics: are variables overwrited when I push a new value?

Question

Let's suppose I'm using the following to indentify some users:

_gaq.push(['_setCustomVar', 1, 'id', '<?php echo time() ?>', 1]);

If I put this snippet on all of my pages, will the id be overwritten every time?

OBS: I'm using a Visitor Scope (1) custom variable.

Answer 1

They will be overwritten when you use the same slot in the same scope, plus there will be problems when you use page level scope variables and other scopes with the same slot on the same page (see https://developers.google.com/analytics/devguides/collection/gajs/gaTrackingCustomVariables#setup - Section "Use Caution When Mixing Different Variable Types").