I'm currently using KNIME Analytics Platform and constantly face different unique values limits whether i'm trying to count simple statistics or create a simple pie chart.
I'd really like to know - do these limits exist for other versions of KNIME, like for KNIME TeamSpace, KNIME Server or any other?
The default number of possible values per string (nominal) column is 60. You can change the limit per column by using the Domain Calculator node. In principle you can set the limit arbitrarily high, but since the possible values are all stored in memory this may get you into trouble if you have lots of them.