openGauss每日一练第3天 | 学习心得体会

学习目标

学习openGauss体系结构，了解实例（集簇或服务）和数据库的关系

1.连接数据库

omm@modb:~$ gsql -r
gsql ((openGauss 3.0.0 build 02c14696) compiled at 2022-04-01 18:12:00 commit 0 last mr  )
Non-SSL connection (SSL connection is recommended when requiring high-security)
Type "help" for help.

2.创建表空间，并在该表空间上创建多个数据库

CREATE TABLESPACE
omm=# CREATE DATABASE musicdb  WITH TABLESPACE = music_tbs;
CREATE DATABASE
omm=# CREATE DATABASE musicdb1 WITH TABLESPACE = music_tbs;
CREATE DATABASE
omm=# CREATE DATABASE musicdb2 WITH TABLESPACE = music_tbs;
CREATE DATABASE
omm=# CREATE DATABASE musicdb3 WITH TABLESPACE = music_tbs;
CREATE DATABASE

3 查看openGauss数据库上有哪些表空间：

omm=#            List of tablespaces
    Name    | Owner |      Location       
------------+-------+---------------------
 music_tbs  | omm   | tablespace/test_ts1
 pg_default | omm   | 
 pg_global  | omm   | 

\l
                         List of databases
   Name    | Owner | Encoding | Collate | Ctype | Access privileges 
-----------+-------+----------+---------+-------+-------------------
 musicdb   | omm   | UTF8     | C       | C     | 
 musicdb1  | omm   | UTF8     | C       | C     | 
 musicdb2  | omm   | UTF8     | C       | C     | 
 musicdb3  | omm   | UTF8     | C       | C     | 
 omm       | omm   | UTF8     | C       | C     | 
 postgres  | omm   | UTF8     | C       | C     | 
 template0 | omm   | UTF8     | C       | C     | =c/omm           +
           |       |          |         |       | omm=CTc/omm
 template1 | omm   | UTF8     | C       | C     | =c/omm           +
           |       |          |         |       | omm=CTc/omm

4 查看openGauss数据库上实例的进程、线程

omm          1     0  0 21:38 ?        00:00:07 gaussdb
omm        503   497  0 22:04 pts/1    00:00:00 sh -c ps -ef|grep gaussdb
omm        505   503  0 22:04 pts/1    00:00:00 grep gaussdb
omm=# \! ps -Tp 1
  PID  SPID TTY          TIME CMD
    1     1 ?        00:00:00 gaussdb
    1   294 ?        00:00:00 jemalloc_bg_thd
    1   300 ?        00:00:00 gaussdb
    1   301 ?        00:00:00 syslogger
    1   302 ?        00:00:00 jemalloc_bg_thd
    1   303 ?        00:00:00 alarm
    1   304 ?        00:00:00 reaper
    1   305 ?        00:00:00 jemalloc_bg_thd
    1   306 ?        00:00:00 jemalloc_bg_thd
    1   350 ?        00:00:00 checkpointer
    1   351 ?        00:00:00 Spbgwriter
    1   352 ?        00:00:01 pagewriter
    1   353 ?        00:00:00 pagewriter
    1   354 ?        00:00:00 pagewriter
    1   356 ?        00:00:00 pagewriter
    1   355 ?        00:00:00 pagewriter
    1   357 ?        00:00:00 WALwriter
    1   358 ?        00:00:00 WALwriteraux
    1   359 ?        00:00:00 AVClauncher
    1   360 ?        00:00:00 Jobscheduler
    1   361 ?        00:00:00 asyncundolaunch
    1   362 ?        00:00:00 globalstats
    1   363 ?        00:00:00 applylauncher
    1   364 ?        00:00:00 statscollector
    1   365 ?        00:00:00 percentworker
    1   366 ?        00:00:02 ashworker
    1   367 ?        00:00:00 TrackStmtWorker
    1   368 ?        00:00:00 auditor
    1   369 ?        00:00:00 2pccleaner
    1   371 ?        00:00:00 WLMworker
    1   370 ?        00:00:00 faultmonitor
    1   372 ?        00:00:00 WLMmonitor
    1   373 ?        00:00:00 WLMarbiter
    1   498 ?        00:00:00 worker
    1   374 ?        00:00:00 undorecycler