首先称赞一下这个活动，学习很方便。每天打卡还可以督促自己学习。
以下是今天的练习内容：
1.从操作系统层面查看数据库进程和线程,判断数据库是否启动。
omm@modb:/var/lib/opengauss/data$ ps -ef |grep -i gauss
omm 1 0 0 10:15 ? 00:00:51 gaussdb
omm 1227 547 0 13:31 pts/0 00:00:00 grep -i gauss
omm@modb:/var/lib/opengauss/data$ ps -Tp 1
PID SPID TTY TIME CMD
1 1 ? 00:00:00 gaussdb
1 288 ? 00:00:00 jemalloc_bg_thd
1 294 ? 00:00:00 gaussdb
1 295 ? 00:00:00 syslogger
1 296 ? 00:00:00 jemalloc_bg_thd
1 297 ? 00:00:01 alarm
1 298 ? 00:00:00 reaper
1 299 ? 00:00:00 jemalloc_bg_thd
1 300 ? 00:00:00 jemalloc_bg_thd
1 344 ? 00:00:00 checkpointer
1 345 ? 00:00:00 Spbgwriter
1 346 ? 00:00:07 pagewriter
1 347 ? 00:00:00 pagewriter
1 348 ? 00:00:00 pagewriter
1 349 ? 00:00:00 pagewriter
1 350 ? 00:00:00 pagewriter
1 351 ? 00:00:00 WALwriter
1 352 ? 00:00:00 WALwriteraux
1 353 ? 00:00:00 AVClauncher
1 354 ? 00:00:00 Jobscheduler
1 355 ? 00:00:00 asyncundolaunch
1 356 ? 00:00:00 globalstats
1 358 ? 00:00:00 statscollector
1 357 ? 00:00:00 applylauncher
1 359 ? 00:00:06 percentworker
1 360 ? 00:00:21 ashworker
1 362 ? 00:00:00 auditor
1 361 ? 00:00:04 TrackStmtWorker
1 363 ? 00:00:00 2pccleaner
1 364 ? 00:00:00 faultmonitor
1 365 ? 00:00:00 WLMworker
1 366 ? 00:00:01 WLMmonitor
1 367 ? 00:00:00 WLMarbiter
1 368 ? 00:00:00 undorecycler
1 1221 ? 00:00:00 worker
2.使用gs_ctl工具查看数据库状态,判断数据库是否启动。
omm@modb:/var/lib/opengauss/data$ gs_ctl status
[2022-11-24 13:33:03.406][1233][][gs_ctl]: gs_ctl status,datadir is /var/lib/opengauss/data
gs_ctl: server is running (PID: 1)
/usr/local/opengauss/bin/gaussdb
3.使用gs_ctl 查看数据文件的目录
omm@modb:/var/lib/opengauss/data$ gs_ctl notify
[2022-11-24 13:33:44.630][1241][][gs_ctl]: gs_ctl notify ,datadir is /var/lib/opengauss/data
[2022-11-24 13:33:44.630][1241][][gs_ctl]: the parameter of notify must be specified
4.从环境变量查看数据文件的目录
omm@modb:/var/lib/opengauss/data$ grep -i PGDATA ~/.bashrc
export PGDATA=/var/lib/opengauss/data
5.在gsql中查看数据文件目录、数据库版本
omm@modb:/var/lib/opengauss/data$ 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.omm=# show data_directory;
data_directory
-------------------------
/var/lib/opengauss/data
(1 row)omm=# select version();
version
-------------------------------------------------------------------------------------------------------------------------------------------------------
(openGauss 3.0.0 build 02c14696) compiled at 2022-04-01 18:12:00 commit 0 last mr on aarch64-unknown-linux-gnu, compiled by g++ (GCC) 7.3.0, 64-bit
(1 row)
