RE: Implement UNLOGGED clause for COPY FROM

From: Amit Kapila <amit(dot)kapila16(at)gmail(dot)com>
> Sure, but on a daily basis, one requires only incremental WAL to
> complete the backup but in this case, it would require the entire
> database back up unless we have some form of block-level incremental
> backup method.

Regarding the backup time, I think users can shorten it by using the storage device's snapshoting (or split mirroring?), filesystem's snapshot feature.

> OTOH, I don't deny that there is some use case with
> wal_level = 'none' for initial data loading as MySQL provides but I
> think that is a separate feature than what is proposed here (Copy
> Unlogged). It might be better if you can start a separate thread for
> that with some more details on the implementation side as well.

Yeah, the feature doesn't match the title of this thread and could confuse other readers that join later. Nevertheless, I think MySQL's feature could be used for additional data loading as well if the user understands what he/she is doing. So, we can discuss it in another thread just in case the ongoing discussion gets stuck.

Regards
Takayuki Tsunakawa