On Wed, Mar 20, 2024 at 7:03 AM Daniel Gustafsson <dan...@yesql.se> wrote: > The issue here is that postgres use a different epoch from the unix epoch, so > any dates calcuated based on the unix epoch need to be adjusted.
Ah, thank you! I had just reproduced Cary's problem and was really confused... > I've hacked > this up in the attached v11 using overflow-safe integer mul/add as proposed by > Jacob upthread (we really shouldn't risk overflowing an int64 here but there > is > no harm in using belts and suspenders here as a defensive measure). > > The attached v11 is what I propose we go ahead with unless there further > comments on this. One last question: > + result -= ((POSTGRES_EPOCH_JDATE - UNIX_EPOCH_JDATE) * USECS_PER_DAY); > + return TimestampTzGetDatum(result); Is that final bare subtraction able to wrap around for dates far in the past? --Jacob
