postgresql常见命令及操作

data
├── global                # under global, all the filenode is hard-code(select oid,relname,relfilenode from pg_class where relfilenode=0 order by oid;)
│   ├── 1136              # pg_pltemplate
│   ├── 1137              # pg_pltemplate_name_index
│   ├── 1213              # pg_tablespace
│   ├── 1214              # pg_shdepend
│   ├── 1232              # pg_shdepend_depender_index
│   ├── 1233              # pg_shdepend_reference_index
│   ├── 1260              # pg_authid
│   ├── 1261              # pg_auth_members
│   ├── 1262              # pg_database
│   ├── 2396              # pg_shdescription
│   ├── 2397              # pg_shdescription_o_c_index
│   ├── 2671              # pg_database_datname_index
│   ├── 2672              # pg_database_oid_index
│   ├── 2676              # pg_authid_rolname_index
│   ├── 2677              # pg_authid_oid_index
│   ├── 2694              # pg_auth_members_role_member_index
│   ├── 2695              # pg_auth_members_member_role_index
│   ├── 2697              # pg_tablespace_oid_index
│   ├── 2698              # pg_tablespace_spcname_index
│   ├── 2846              # pg_toast_2396
│   ├── 2847              # pg_toast_2396_index
│   ├── 2964              # pg_db_role_setting
│   ├── 2965              # pg_db_role_setting_databaseid_rol_index
│   ├── 2966              # pg_toast_2964
│   ├── 2967              # pg_toast_2964_index
│   ├── 3592              # pg_shseclabel
│   ├── 3593              # pg_shseclabel_object_index
│   ├── 4060              # pg_toast_3592x
│   ├── 4061              # pg_toast_3592_index
│   ├── 6000              # pg_replication_origin
│   ├── 6001              # pg_replication_origin_roiident_index
│   ├── 6002              # pg_replication_origin_roname_index
│   ├── pg_control        # global control file, use pgcheck -pc to see it.
│   ├── pg_filenode.map   # system table (oid -> filenode) mapping file, use pgcheck -pm to see it.
│   └── pg_internal.init  # system table cache file, use pgcheck -pr to see it.

#------------------------------------------------------------------------------
# FILE LOCATIONS
#------------------------------------------------------------------------------

# The default values of these variables are driven from the -D command-line
# option or PGDATA environment variable, represented here as ConfigDir.

#data_directory = 'ConfigDir'           # use data in another directory
                                        # (change requires restart)
#hba_file = 'ConfigDir/pg_hba.conf'     # host-based authentication file
                                        # (change requires restart)
#ident_file = 'ConfigDir/pg_ident.conf' # ident configuration file
                                        # (change requires restart)

# If external_pid_file is not explicitly set, no extra PID file is written.
#external_pid_file = ''                 # write an extra PID file
                                        # (change requires restart)


#------------------------------------------------------------------------------
# CONNECTIONS AND AUTHENTICATION
#------------------------------------------------------------------------------

# - Connection Settings -

listen_addresses = 'localhost'          # what IP address(es) to listen on;
                                        # comma-separated list of addresses;
                                        # defaults to 'localhost'; use '*' for all
                                        # (change requires restart)
port = 5432                             # (change requires restart)
max_connections = 100                   # (change requires restart)
#superuser_reserved_connections = 3     # (change requires restart)

# It's not recommended to modify this file in-place, because it will be
# overwritten during package upgrades.  If you want to customize, the
# best way is to create a file "/etc/systemd/system/postgresql-10.service",
# containing
#       .include /lib/systemd/system/postgresql-10.service
#       ...make your changes here...
# For more info about custom unit files, see
# http://fedoraproject.org/wiki/Systemd#How_do_I_customize_a_unit_file.2F_add_a_custom_unit_file.3F

# Note: changing PGDATA will typically require adjusting SELinux
# configuration as well.

# Note: do not use a PGDATA pathname containing spaces, or you will
# break postgresql-setup.
[Unit]
Description=PostgreSQL 10 database server
Documentation=https://www.postgresql.org/docs/10/static/
After=syslog.target
After=network.target

[Service]
Type=notify
User=postgres
Group=postgres

# Note: avoid inserting whitespace in these Environment= lines, or you may
# break postgresql-setup.

# Location of database directory
Environment=PGDATA=/home/pgsql/data/

# Where to send early-startup messages from the server (before the logging
# options of postgresql.conf take effect)
# This is normally controlled by the global default set by systemd
# StandardOutput=syslog

# Disable OOM kill on the postmaster
OOMScoreAdjust=-1000
Environment=PG_OOM_ADJUST_FILE=/proc/self/oom_score_adj
Environment=PG_OOM_ADJUST_VALUE=0

ExecStartPre=/usr/pgsql-10/bin/postgresql-10-check-db-dir ${PGDATA}
ExecStart=/usr/pgsql-10/bin/postmaster -D ${PGDATA}
ExecReload=/bin/kill -HUP $MAINPID
KillMode=mixed
KillSignal=SIGINT


# Do not set any timeout value, so that systemd will not kill postmaster
# during crash recovery.
TimeoutSec=0

[Install]
WantedBy=multi-user.target