"Magnus Hagander" <mha(at)sollentuna(dot)net> writes:
>> Someone in this group mentioned a while back that
>> pg_backend_pid() function works only after some 1/2 second
>> after the connection has been established.
> No, pg_backend_pid() returns MyProcPid, which is set on backend startup.
> However, the different pg_stat_* views won't work until a message has
> been passed down to the stats collector, that is correct.
That is to say, in existing releases there'll be a delay before a row
for your session is visible in pg_stat_activity. This problem will
go away in 8.2 though, because the mechanism for pg_stat_activity was
redone (the other pg_stat_* views still have a delay, but it's less
critical for them).
regards, tom lane