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HomeDatabaseMysql Tutorial在做到3.1数据库查询时需要注意的地方

DEMO10 (数据库查询) 自:首先要用命令 oninit 一下,表示启动informix数据库 然后才能照着手册上的接着 onstat - 查看 网址:http://www.chinaunix.net/bbsjh/9/420.html 网上搜的结果如下: [原创]Informix命令之一--oninit Usage: oninit { -[ipsy] }

DEMO10(数据库查询)
自:首先要用命令 oninit  一下,表示启动informix数据库
然后才能照着手册上的接着 onstat -  查看

网址:http://www.chinaunix.net/bbsjh/9/420.html
网上搜的结果如下:
[原创]Informix命令之一--oninit
Usage: oninit { -[ipsy] }

    -i   Initialize disk space and shared memory, leave in on-line mode.
    -p   Do not reclaim temporary tables.
    -s   Initialize shared memory, leave in quiescent mode.
    -y   Respond yes to all prompts

以上是在线帮助,用法如下:
 1)$>oninit -i
    这个命令将初始化磁盘空间,是很危险的参数,在你使用数据库的过程中,只能在刚安装完做一次,否则。。。
 2)$>oninit -p
    数据库不正常宕掉时,数据库中会留有临时表,这些表会占据一定的磁盘空间,一般我们重起数据库时,数据库会自动删除临时表,但我们也可以使用该命令保留这些临时表。
 3)$>oninit -s
    将数据库服务器启动到单用户模式,就同操作系统的单用户一样,这时你可以做一些维护工作,而不受其它想连上数据库的用户干扰。
 4) $>oninit
   正常启动数据库。
 5)$>oninit -v
   正常启动数据库,并且显示启动的过程信息。
   


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