On Thu, Nov 1, 2018 at 1:49 PM Ravi Krishna <srkrish...@aol.com> wrote:
> Per documentation unlogged tables are not crash safe and PG will truncate > it when it restarts after a crash. Does this apply to even read only > unlogged tables. > > For example: > > On Monday I load data into unlogged tables. > > Then from Tue onwards the table is only read by application. > > On Fri morning PG crashes. When it restarts will it truncate all unlogged > tables even though they remained > unchanged. I hope it does not. "an unlogged table is automatically truncated after a crash or unclean shutdown." - there are no exceptions noted. There is no such thing as a "read only" table in PostgreSQL. All tables are read/write no matter that frequency of either event. There is nothing inherently special about "no writes for 4 days" and "no writes for 10 seconds" that would allow for a distinction to be made. There could be write in progress on the table just as it crashes Friday. David J.
