Also, you should have MP tests that make sure the same value is used on different partitions -- for example, insert multiple rows (values not important) in a partitioned table and then "select NOW() from P1" to make sure you get the same value from all partitions.

Similarly, update all the rows of a partitioned table setting a column to now or to EXTRACT(MILLIS, NOW). Then do a group by query on the updated column to make sure they all end up in one group.

You should add a stored proc test like we discussed to make sure that the NOW value is stable within a transaction.