postgresql相关

centos7安装postgresql，yum install postgresql，版本是9.2.7

安装后，初始化数据库

/usr/pgsql-9.6/bin/postgresql96-setup initdb   //根据具体版本来

然后（这里参考https://blog.csdn.net/DaSo_CSDN/article/details/75330009）

systemctl enable postgresql

systemctl start postgresql失败，

systemctl status postgresql提示要先初始化数据库，日志中有命令

查看服务启动脚本/usr/lib//usr/lib/systemd/system/postgresql.service，当中:

约定了data目录PGDATA=/var/lib/pgsql/data和监听端口PGPORT=5432

----------------------------------11版本安装--------------------------------------------

# 下载rpm包
yum install https://download.postgresql.org/pub/repos/yum/11/redhat/rhel-7-x86_64/pgdg-redhat11-11-2.noarch.rpm -y

# 安装
yum -y install postgresql11 postgresql11-server postgresql11-libs

# 初始化数据库
/usr/pgsql-11/bin/postgresql-11-setup initdb

# 设置开机自启动PostgreSQL和启动服务
systemctl enable postgresql-11
systemctl start postgresql-11
systemctl status postgresql-11

---------------------------------wsl 11安装-------------------------------------------------------------

sudo apt-get install wget ca-certificates
wget --quiet -O - https://www.postgresql.org/media/keys/ACCC4CF8.asc | sudo apt-key add -
sudo sh -c 'echo "deb http://apt.postgresql.org/pub/repos/apt/ `lsb_release -cs`-pgdg main" >> /etc/apt/sources.list.d/pgdg.list'
sudo apt-get update
sudo apt-get install postgresql postgresql-contrib #默认安装两个版本
sudo service postgresql start  #默认启动两个版本

/etc/postgresql/版本/main/是配置文件目录，修改postgresql.conf，将11版本的端口改成5432，10版本的改为5433

sudo service postgresql start 11 #启动11版本

from:https://www.jianshu.com/p/018922b9ad31

and:https://www.jianshu.com/p/0dea2a45e2de

---------------------------------------------------------------------------------------------------------------

到data目录下

修改postgresql.conf，查找#listen_addresses = 'localhost'，改成

listen_addresses = '*'

修改pg_hba.conf，IPV4连接，改成这样

# IPv4 local connections:
host    all             all             127.0.0.1/32            trust
host    all             all             0.0.0.0/0               password

参考
https://www.cnblogs.com/qiyebao/p/4562557.html

trust，本地可以使用psql -U postgres直接登录服务器；
peer，本地可以使用psql -h 127.0.0.1 -d postgres -U postgres直接登录服务器；

本地登录：

psql -U postgres //连接pgsql server
psql -h 127.0.0.1 -d postgres -U postgres //连接pgsql server

刷新配置

select pg_reload_conf();

显示一个新配置：

show data_directory;

为默认数据库账户postgres设置密码

select * from pg_shadow;

ALTER USER postgres WITH PASSWORD '1234'; //添加密码
select * from pg_shadow;
q回车 退出登录

防火墙打开5432端口

iptables -I INPUT -p tcp --dport 5432 -j ACCEPT
service iptables save
service iptables restart

 ----------------------操作数据库实例------------------------

https://blog.csdn.net/skh2015java/article/details/78814774

https://o-my-chenjian.com/2018/11/24/CRUD-Of-PostgreSQL-By-Golang/

https://blog.csdn.net/u013210620/article/details/82702114#GoPostgreSQLgithubcomlibpq_193

https://segmentfault.com/a/1190000018812714

-----------------------------------

监控指标的一个说明

https://www.influxdata.com/blog/metrics-to-monitor-in-your-postgresql-database/