数据库的简单使用
启动/停止数据库服务
通常情况下，使用 gbasedbt 用户来启动和停止数据库服务。
成功安装数据库 GBase 8s 后，数据库会自动处于启动状态，可通过 ps -ef|grep oninit 命令检查服务进程是否存在：
[root@localhost opt]# ps -ef|grep oninit
gbasedbt 10830 1 0 19:52 ? 00:00:04 /opt/GBASE/gbase/bin/oninit -vy
root 10831 10830 0 19:52 ? 00:00:00 /opt/GBASE/gbase/bin/oninit -vy
root 10832 10831 0 19:52 ? 00:00:00 /opt/GBASE/gbase/bin/oninit -vy
root 10833 10831 0 19:52 ? 00:00:00 /opt/GBASE/gbase/bin/oninit -vy
root 10834 10831 0 19:52 ? 00:00:00 /opt/GBASE/gbase/bin/oninit -vy
root 10835 10831 0 19:52 ? 00:00:00 /opt/GBASE/gbase/bin/oninit -vy
root 10836 10831 0 19:52 ? 00:00:00 /opt/GBASE/gbase/bin/oninit -vy
root 10837 10831 0 19:52 ? 00:00:00 /opt/GBASE/gbase/bin/oninit -vy
root 10915 10831 0 19:52 ? 00:00:00 /opt/GBASE/gbase/bin/oninit -vy
root 11997 5051 0 20:02 pts/0 00:00:00 grep oninit
以 gbasedbt 用户身份登录后，执行 onmode -ky，可停止数据库服务，示例如下：
[gbasedbt@localhost ~]$ onmode -ky
执行 oninit -vy, 启动数据库服务，示例如下：
[gbasedbt@localhost ~]$ oninit -vy
Warning: Parameter's user-configured value was adjusted. (DS_MAX_SCANS)
Warning: Parameter's user-configured value was adjusted. (ONLIDX_MAXMEM)
Reading configuration file '/opt/GBASE/gbase/etc/onconfig.ol_gbasedbt1210'...succeeded
Creating /GBASEDBTTMP/.infxdirs...succeeded
Allocating and attaching to shared memory...succeeded
Creating resident pool 8310 kbytes...succeeded
Creating infos file "/opt/GBASE/gbase/etc/.infos.ol_gbasedbt1210"...succeeded
Linking conf file "/opt/GBASE/gbase/etc/.conf.ol_gbasedbt1210"...succeeded
Initializing rhead structure...rhlock_t 16384 (512K)... rlock_t (5312K)... Writing to infos file...succeeded
Initialization of Encryption...succeeded
Initializing ASF...succeeded
Initializing Dictionary Cache and SPL Routine Cache...succeeded
Bringing up ADM VP...succeeded
Creating VP classes...succeeded
Forking main_loop thread...succeeded
Initializing DR structures...succeeded
Forking 1 'soctcp' listener threads...succeeded
Forking 1 'soctcp' listener threads...succeeded
Forking 1 'soctcp' listener threads...succeeded
Starting tracing...succeeded
Initializing 2 flushers...succeeded
Initializing SDS Server network connections...succeeded
Initializing log/checkpoint information...succeeded
Initializing dbspaces...succeeded
Opening primary chunks...succeeded
Validating chunks...succeeded
Initialize Async Log Flusher...succeeded
Starting B-tree Scanner...succeeded
Init ReadAhead Daemon...succeeded
Init DB Util Daemon...succeeded
Initializing DBSPACETEMP list...succeeded
Init Auto Tuning Daemon...succeeded
Checking database partition index...succeeded
Initializing dataskip structure...succeeded
Checking for temporary tables to drop...succeeded
Updating Global Row Counter...succeeded
Forking onmode_mon thread...succeeded
Creating periodic thread...succeeded
Creating periodic thread...succeeded
Starting scheduling system...succeeded
Verbose output complete: mode = 5
启动成功后，输入 ps -ef|grep oninit 检查数据库服务进程存在：
[gbasedbt@localhost ~]$ ps -ef|grep oninit
gbasedbt 12056 1 0 20:14 ? 00:00:00 oninit -vy
root 12057 12056 0 20:14 ? 00:00:00 oninit -vy
root 12058 12057 0 20:14 ? 00:00:00 oninit -vy
root 12059 12057 0 20:14 ? 00:00:00 oninit -vy
root 12060 12057 0 20:14 ? 00:00:00 oninit -vy
root 12061 12057 0 20:14 ? 00:00:00 oninit -vy
root 12062 12057 0 20:14 ? 00:00:00 oninit -vy
root 12063 12057 0 20:14 ? 00:00:00 oninit -vy
root 12064 12057 0 20:14 ? 00:00:00 oninit -vy
gbasedbt 12134 12116 0 20:25 pts/0 00:00:00 grep oninit
登录数据库
以 gbasedbt 用户身份登录，输入 dbaccess - - 命令进入数据库命令行模式，示例如下：
[gbasedbt@localhost ~]$ dbaccess - -
>
创建数据库
[gbasedbt@localhost~]$ dbaccess - -
> create database gbase8s with log;
Database created.