Thread: tup_returned/ tup_fetched
Hi,
one question:
what actually is tup_returned and tup_fetched ?
read from disc before scans and before aggregate ?
thanks
sebastian
Sebastian Böhm <seb@exse.net> writes: > one question: > > what actually is tup_returned and tup_fetched ? RTFM -- admittedly it's not so easy to find these since you have to know they come from the following functions: pg_stat_get_tuples_returned(oid) bigint Number of rows read by sequential scans when argument is a table, or number of index entries returned when argument is an index pg_stat_get_tuples_fetched(oid) bigint Number of table rows fetched by bitmap scans when argument is a table, or table rows fetched by simple index scans using the index when argument is an index From: http://www.postgresql.org/docs/8.3/interactive/monitoring-stats.html -- Gregory Stark EnterpriseDB http://www.enterprisedb.com Get trained by Bruce Momjian - ask me about EnterpriseDB's PostgreSQL training!
sorry I was not very precise. My question is what does it actually mean in the end for these two functions: pg_stat_get_db_tuples_returned(oid) bigint Number of tuples returned for database pg_stat_get_db_tuples_fetched(oid) bigint Number of tuples fetched for database I read the description below, but I don't completely understand the difference. I want to plot a realtime graph: "tuples read from buffers or disk" is it both combined ? Thanks Sebastian Am 15.12.2008 um 04:28 schrieb Gregory Stark: > Sebastian Böhm <seb@exse.net> writes: > >> one question: >> >> what actually is tup_returned and tup_fetched ? > > RTFM -- admittedly it's not so easy to find these since you have to > know they > come from the following functions: > > > pg_stat_get_tuples_returned(oid) bigint Number of rows read by > sequential > scans when argument is a table, or number of index entries returned > when > argument is an index > > pg_stat_get_tuples_fetched(oid) bigint Number of table rows fetched > by bitmap > scans when argument is a table, or table rows fetched by simple > index scans > using the index when argument is an index > > From: > > http://www.postgresql.org/docs/8.3/interactive/monitoring-stats.html > > -- > Gregory Stark > EnterpriseDB http://www.enterprisedb.com > Get trained by Bruce Momjian - ask me about EnterpriseDB's > PostgreSQL training! >
El Martes, 16 de Diciembre de 2008 04:02:09 Sebastian Böhm escribió: > sorry I was not very precise. > > My question is what does it actually mean in the end for these two > functions: > > pg_stat_get_db_tuples_returned(oid) bigint Number of tuples returned > for database > pg_stat_get_db_tuples_fetched(oid) bigint Number of tuples fetched for > database > > I read the description below, but I don't completely understand the > difference. > From 8.2 docs pg_stat_get_tuples_returned(oid) bigint Number of rows read by sequential scans when argument is a table, or number of index entries returned when argument is anindex pg_stat_get_tuples_fetched(oid) bigint Number of table rows fetched by bitmap scans when argument is a table, or table rows fetched by simple index scans usingthe index when argument is an index > I want to plot a realtime graph: "tuples read from buffers or disk" > is it both combined ? > > > Thanks > Sebastian > > > > > Am 15.12.2008 um 04:28 schrieb Gregory Stark: > > > Sebastian Böhm <seb@exse.net> writes: > > > >> one question: > >> > >> what actually is tup_returned and tup_fetched ? > > > > RTFM -- admittedly it's not so easy to find these since you have to > > know they > > come from the following functions: > > > > > > pg_stat_get_tuples_returned(oid) bigint Number of rows read by > > sequential > > scans when argument is a table, or number of index entries returned > > when > > argument is an index > > > > pg_stat_get_tuples_fetched(oid) bigint Number of table rows fetched > > by bitmap > > scans when argument is a table, or table rows fetched by simple > > index scans > > using the index when argument is an index > > > > From: > > > > http://www.postgresql.org/docs/8.3/interactive/monitoring-stats.html > > > > -- > > Gregory Stark > > EnterpriseDB http://www.enterprisedb.com > > Get trained by Bruce Momjian - ask me about EnterpriseDB's > > PostgreSQL training! > > > > -- No imprima este correo si no es necesario. El medio ambiente está en nuestras manos. __________________________________________ Clist UAH a.k.a Angel __________________________________________ "Te has metido en un hipoteca de 70M y encima te roban una panda de Ninjas... Crisis Ninja para Dummies