On Mon, Mar 25, 2024 at 8:46 PM Bertrand Drouvot <bertranddrouvot...@gmail.com> wrote: > > On Mon, Mar 25, 2024 at 08:38:16PM +0530, Amit Kapila wrote: > > On Mon, Mar 25, 2024 at 7:51 PM Robert Haas <robertmh...@gmail.com> wrote: > > > > > > On Mon, Mar 25, 2024 at 10:02 AM Amit Kapila <amit.kapil...@gmail.com> > > > wrote: > > > > We considered the other two names as last_inactive_at and > > > > last_active_time. For the first (last_inactive_at), there was an > > > > argument that most other fields that display time ends with _time. For > > > > the second (last_active_time), there was an argument that it could be > > > > misleading as one could think that it should be updated each time WAL > > > > record decoding is happening [1]. The other possibility is to name it > > > > last_used_time but I think it won't be much different from > > > > last_active_time. > > > > > > I don't understand the bit about updating it each time WAL record > > > decoding is happening. If it's the last active time, and the slot is > > > currently active, then the answer is either "right now" or "currently > > > undefined." I'd expect to see NULL in the system view in such a case. > > > And if that's so, then there's nothing to update each time a record is > > > decoded, because it's just still going to show NULL. > > > > > > > IIUC, Bertrand's point was that users can interpret last_active_time > > as a value that gets updated each time they decode a change which is > > not what we are doing. So, this can confuse users. Your expectation of > > answer (NULL) when the slot is active is correct and that is what will > > happen. > > Yeah, and so would be the confusion: why is last_active_time NULL while one is > using the slot? >
It is because we set it to zero when we acquire the slot and that value will remain the same till the slot is active. I am not sure if I understood your question so what I am saying might not make sense. -- With Regards, Amit Kapila.
