Postgresql 学习笔记 （还在对postgresql迷茫的xdjm有福啦～～）

1. In a terminal:

$ psql

2. Get into a postgresql with role "postgres", then create a user "db"

postgres-# create role dbcreator with password 'nifti';

3. Change user to postgres

$ sudo su postgres
postgres@computername:/home/$ sudo su postgres

4. Create db mydb and get into mydb

postgres@computername:/home/$ psql
postgres=# create database mydb with owner=dbcreator;

How to get help :

	postgres=# \h create database

5. 返回username用户下，进入mydb

username@computername:/home/db$ psql -d mydb

mydb=#

6. search commands:

mdb=# \?

7. Check table in mydb

mdb=# \d

8. Then we know \i can run a file 

mydb=\i createdummy.sql

9. At last, we create a table for storage a ROS bag data, and we retrieval data by its id, topic, type, sizeoftopic or target.

*/db $ python extract* *.bag

10. Make the database can be accessed by remote users