Module13_Data_Dictionaries

Question 1

where are the data dictonary objects stored

Answer 1

pg_catalog or \dS

Question 2

what is stored in pg_file_settings

Answer 2

contents op postgresql.conf

Question 3

what is stored in pg_policy

Answer 3

stores row level security for tables

Question 4

what is stored in pg_policies

Answer 4

Provides acces to usefull info about each row-level secuirty in DB

Question 5

pg_*_size
pg_column_size
pg_size_pretty
pg_ls_dir,pg_read_file
pg_blocking_pids()

Answer 5

pg_*_size: diskspace used by DB,schema,tablespace

pg_column_size: bytes used to store value

pg_size_pretty: convert raw size to hum an readable

pg_ls_dir,pg_read_file: file operation function restricted to superuser.

pg_blocking_pids(): function to find blocking sessions

Question 6

pg_stat_activiry
pg_locks
pg_stat_database
pg_stat_user_*
pg_stat_archiver
pg_stat_progress_basebackup
pg_stat_progress_vacuum
pg_stat_progress_analyze
pg_hba_file_rules

Answer 6

details of open connections and transactions
list of current locks being held
details of databases
details of tables, indexes and functions
status of archiver process
view pg_basebackup progress
show progress report for vacuum ops
show progress report for analyze ops
provides summary of pg_hba.conf

Question 7

how to get output better readable in psql

Answer 7

\x

Question 8

how to force log switch

Answer 8

select pg_switch_wal();

Question 9

how to kill session

Answer 9

pg_terminate_backend()