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DACS 7.x Postgrees query "vacum" what function is this in DACS?

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This is information from DACS support team.

vacuum is a normal function within Postgres and is not linked to a specific function in DACS .

Description:
VACUUM reclaims storage occupied by dead tuples. In normal PostgreSQL operation, tuples that are deleted or obsoleted by an update are not physically removed from their table; they remain present until a VACUUM is done. Therefore it's necessary to do VACUUM periodically, especially on frequently-updated tables.

You can find more details in the internet like here for example:
https://www.postgresql.org/docs/9.1/sql-vacuum.html

The vacuum/autovacuum can be configured in the postgres config file $DACS_HOME/pgsql/data/postgres.conf or wherever your postgres is installed.

Per default autovacuum is turned on and if you want to turn it off or change its behavior you have to uncomment the parameter and set it accordingly followed by dacs station and postrges restart.

Default values in postgres.conf of my system:
#------------------------------------------------------------------------------
# AUTOVACUUM
#------------------------------------------------------------------------------

#autovacuum = on # Enable autovacuum subprocess? 'on'
# requires track_counts to also be on.
#log_autovacuum_min_duration = -1 # -1 disables, 0 logs all actions and
# their durations, > 0 logs only
# actions running at least this number
# of milliseconds.
#autovacuum_max_workers = 3 # max number of autovacuum subprocesses
# (change requires restart)
#autovacuum_naptime = 1min # time between autovacuum runs
#autovacuum_vacuum_threshold = 50 # min number of row updates before
# vacuum
#autovacuum_analyze_threshold = 50 # min number of row updates before
# analyze
#autovacuum_vacuum_scale_factor = 0.2 # fraction of table size before vacuum
#autovacuum_analyze_scale_factor = 0.1 # fraction of table size before analyze
#autovacuum_freeze_max_age = 200000000 # maximum XID age before forced vacuum
# (change requires restart)
#autovacuum_multixact_freeze_max_age = 400000000 # maximum multixact age
# before forced vacuum
# (change requires restart)
#autovacuum_vacuum_cost_delay = 20ms # default vacuum cost delay for
# autovacuum, in milliseconds;
# -1 means use vacuum_cost_delay
#autovacuum_vacuum_cost_limit = -1 # default vacuum cost limit for
# autovacuum, -1 means use
# vacuum_cost_limit
#------------------------------------------------------------------------------

The following sql command will show you the current vacuum settings in your db:
select * from pg_settings where category like 'Autovacuum';

You can connect to your postgres db with the following command:
psql -Udacs_system -d dacs_main password is dacsdeer

If you disable autovacuum (setting autovacuum = off) you have to take care of running the vacuum command yourself from time to time.

The autovacuum is running every minute per default.
If you want to increase the time interval you have to increase the parameter autovacuum_naptime in the postgres config file.

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Hello @Kevin.Gower

DACS questions should be escalated to DACS support team who can provide the proper answer to you. You can contact the DACS support team by opening a case via Get Product Support in MyRefinitiv. If you face any difficulties to submit the query, please contact Refinitiv account team.

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