bug(timestamp): timestamp mutates after call to `cache` about ibis HOT 2 CLOSED

Ok, first thing, the workaround for this is to explicitly cast the memtable timestamp column to the explicit precision of the backend (assuming you have some operation which is failing because of the schema change after running cache).

As for how to fix this, that isn't totally clear to me, or what TO fix.

A memtable is an expression that has data attached to it. That data is correctly typed when we create the memtable, even if the precision could be more explicit. If we mutate the original memtable upon the cache call, it would keep the schemas of the memtable and the cached version equal, but that means the memtable is now limited to backends that have the same default precision for timestamps (we have a mix of "don't care", timestamp(6), and timestamp(9))

from ibis.

Ehh, I don't think this is a bug. I'm going to close it out.

from ibis.