1, the installation
#yum install -y postgresql-server2, postgresql database initialization
#service postgresql initdb3, start the postgresql service
#systemctl start postgresql
#systemctl enable postgresql4, view the status postgresql
#netstat -tlunp|grep 5432
#ss -tlunp|grep 54325, the database is connected postgresql
want to connect to the database, need to switch to postgres user (by default, automatically generated postgresql installation), use psql connection to the database, the database in which the user is connected, does not require a password.
#查看生成的用户
# tail -1 /etc/passwd
postgres:x:26:26:PostgreSQL Server:/var/lib/pgsql:/bin/bash
#切换用户，登录postgresql
[root@centos7 data]# su - postgres
Last login: Thu Oct 24 16:06:34 CST 2019 on pts/1
-bash-4.2$ psql #使用psql登录数据库
psql (9.2.24)
Type "help" for help.
postgres=# \l #列出所有数据库，相当于show databases;
List of databases
Name | Owner | Encoding | Collate | Ctype | Access privileges
-----------+----------+-----------+---------+-------+-----------------------
postgres | postgres | SQL_ASCII | C | C |
template0 | postgres | SQL_ASCII | C | C | =c/postgres +
| | | | | postgres=CTc/postgres
template1 | postgres | SQL_ASCII | C | C | =c/postgres +
| | | | | postgres=CTc/postgres
(3 rows)
postgres=# \q #退出数据库
-bash-4.2$ 6, postgresql simple configuration
to configure postgresql database mainly by modifying the postgresql.conf file in the data directory to achieve
# ll /var/lib/pgsql/data/ #yum安装时路径
total 48
drwx------. 5 postgres postgres 41 Oct 24 15:49 base
drwx------. 2 postgres postgres 4096 Oct 24 15:50 global
drwx------. 2 postgres postgres 18 Oct 24 15:49 pg_clog
-rw-------. 1 postgres postgres 4232 Oct 24 15:49 pg_hba.conf
-rw-------. 1 postgres postgres 1636 Oct 24 15:49 pg_ident.conf
drwx------. 2 postgres postgres 32 Oct 24 15:49 pg_log
drwx------. 4 postgres postgres 36 Oct 24 15:49 pg_multixact
drwx------. 2 postgres postgres 18 Oct 24 15:50 pg_notify
drwx------. 2 postgres postgres 6 Oct 24 15:49 pg_serial
drwx------. 2 postgres postgres 6 Oct 24 15:49 pg_snapshots
drwx------. 2 postgres postgres 25 Oct 24 16:26 pg_stat_tmp
drwx------. 2 postgres postgres 18 Oct 24 15:49 pg_subtrans
drwx------. 2 postgres postgres 6 Oct 24 15:49 pg_tblspc
drwx------. 2 postgres postgres 6 Oct 24 15:49 pg_twophase
-rw-------. 1 postgres postgres 4 Oct 24 15:49 PG_VERSION
drwx------. 3 postgres postgres 60 Oct 24 15:49 pg_xlog
-rw-------. 1 postgres postgres 19805 Oct 24 15:49 postgresql.conf
-rw-------. 1 postgres postgres 57 Oct 24 15:50 postmaster.opts
-rw-------. 1 postgres postgres 92 Oct 24 15:50 postmaster.pid7, modify the listening ports and Ip
#vim /var/lib/pgsql/data/postgresql.conf
59 #listen_addresses = 'localhost' # what IP address(es) to listen on;
60 # comma-separated list of addresses;
61 # defaults to 'localhost'; use '*' for all
62 # (change requires restart)
63 #port = 5432 # (change requires restart)
修改端口时，默认把前面#去掉，不修改的话默认为5432
#修改完后重启服务
#systemctl restart postgresql8, modify the database log parameters related
# - Where to Log -
#log_destination = 'stderr' # Valid values are combinations of
# stderr, csvlog, syslog, and eventlog,
# depending on platform. csvlog
# requires logging_collector to be on.
# This is used when logging to stderr:
logging_collector = on # Enable capturing of stderr and csvlog
#日志默认为打开
# into log files. Required to be on for
# csvlogs.
# (change requires restart)
# These are only used if logging_collector is on:
#log_directory = 'pg_log' # directory where log files are written,
# can be absolute or relative to PGDATA
log_filename = 'postgresql-%a.log' # log file name pattern,
# can include strftime() escapes
#log_file_mode = 0600 # creation mode for log files,
# begin with 0 to use octal notation
log_truncate_on_rotation = on # If on, an existing log file with the
# same name as the new log file will be
# truncated rather than appended to.
# But such truncation only occurs on
# time-driven rotation, not on restarts
# or size-driven rotation. Default is
# off, meaning append to existing files
# in all cases.
log_rotation_age = 1d # Automatic rotation of logfiles will
#日志只保存一天
# happen after that time. 0 disables.
log_rotation_size = 0 # Automatic rotation of logfiles will
# happen after that much log output.
# 0 disables.9, memory parameter settings
# - Memory -
shared_buffers = 32MB # min 128kB
#共享内存的大小，用于共享数据块10, add users, create a database and log
#授权用户远程登录
#vim /var/lib/pgsql/data/pg_hba.conf #在最后一行添加
host all all 0.0.0.0/0 md5
#vim /var/lib/pgsql/data/postgresql.conf
listen_addresses='*' #把localhost更改为*
#systemctl restart postgresql
#创建用户和密码
postgres=# create user wang01 with password '123456';
CREATE ROLE
#创建数据库，基于用户wang01
postgres=# create database test01 owner wang01;
CREATE DATABE
#授权用户
postgres=# grant all privileges on database test01 to wang01;
GRANT
#查看结果
postgres=# \l
List of databases
Name | Owner | Encoding | Collate | Ctype | Access privileges
-----------+----------+-----------+---------+-------+-----------------------
postgres | postgres | SQL_ASCII | C | C |
template0 | postgres | SQL_ASCII | C | C | =c/postgres +
| | | | | postgres=CTc/postgres
template1 | postgres | SQL_ASCII | C | C | =c/postgres +
| | | | | postgres=CTc/postgres
test | wang | SQL_ASCII | C | C | =Tc/wang +
| | | | | wang=CTc/wang
test01 | wang01 | SQL_ASCII | C | C | =Tc/wang01 +
| | | | | wang01=CTc/wang01
test02 | postgres | SQL_ASCII | C | C |
(6 rows)
#登录
[root@centos7 data]# psql -h 10.0.0.3 -p 5432 -U wang -d test
Password for user wang:
psql (9.2.24)
Type "help" for help.
test=> \l
List of databases
Name | Owner | Encoding | Collate | Ctype | Access privileges
-----------+----------+-----------+---------+-------+-----------------------
postgres | postgres | SQL_ASCII | C | C |
template0 | postgres | SQL_ASCII | C | C | =c/postgres +
| | | | | postgres=CTc/postgres
template1 | postgres | SQL_ASCII | C | C | =c/postgres +
| | | | | postgres=CTc/postgres
test | wang | SQL_ASCII | C | C | =Tc/wang +
| | | | | wang=CTc/wang
(4 rows)11, postgresql database basic application
1、列出所有数据库
mysql: show databases
psql: \l或\list
2、切换数据库
mysql: use dbname
psql: \c dbname
3、列出当前数据库下的所有表
mysql: show tables
psql: \d
4、列出指定表的所有字段
mysql: shwo columns from table_name
psql: \d table_name
5、查看表的基本情况
mysql: describe table_name
psql: \d+ table_name