一）安装
1、安装 PostgreSQL
[root@localhost ~]# docker pull postgres
Using default tag: latest
latest: Pulling from library/postgres
33847f680f63: Pull complete
1b09e96014b3: Pull complete
eb49b6d9d1f3: Pull complete
4057ebf78d2d: Pull complete
f92d870e2c4f: Pull complete
b03847575a18: Pull complete
475945131fa9: Pull complete
c042b5a6607d: Pull complete
cfe883b776dc: Pull complete
61af04e5c3eb: Pull complete
4e9965ae9062: Pull complete
7b9708b81aa6: Pull complete
871877336770: Pull complete
Digest: sha256:6647385dd9ae11aa2216bf55c54d126b0a85637b3cf4039ef24e3234113588e3
Status: Downloaded newer image for postgres:latest
docker.io/library/postgres:latest
#检查是否安装成功
[root@localhost ~]# docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
postgres latest b2fcd079c1d4 2 weeks ago 315MB
jenkins/jenkins latest 171f17febd29 4 months ago 572MB
[root@localhost ~]# docker images | grep postgres
postgres latest b2fcd079c1d4 2 weeks ago 315MB
2.创建容器
docker的容器默认情况下只能由本地主机访问，即A主机上的容器不能被B主机访问，所以要做端口映射
[root@localhost ~]# docker run --name postgres -e POSTGRES_PASSWORD=123456 -p 5432:5432 -d postgres
e238f591a836031104964688110cd49afb2679adc94c69aeab444f5c5ce91bee
解释：
run ：创建并运行一个容器
--name ：指定创建的容器的名字
-e POSTGRES_PASSWORD=password，设置环境变量，指定数据库的登录口令是password；
p 54321:5432，端口映射将容器的5432端口映射到外部机器的54321端口；-d postgres，指定使用 postgres 作为镜像
2.1验证结果
[root@localhost ~]# docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
e238f591a836 postgres "docker-entrypoint.s…" 9 seconds ago Up 7 seconds 0.0.0.0:5432->5432/tcp, :::5432->5432/tcp postgres
3a0c5a912f71 jenkins/jenkins "/sbin/tini -- /usr/…" 3 months ago Exited (255) 45 minutes ago 50000/tcp, 0.0.0.0:8888->8080/tcp, :::8888->8080/tcp jenkins1
3、连接数据库，进入psql命令行
[root@localhost ~]# docker exec -it postgres /bin/bash
root@e238f591a836:/# psql -U postgres -W
Password:
psql (13.3 (Debian 13.3-1.pgdg100+1))
Type "help" for help.