实例的概念 Every running Oracle database is associated with an Oracle instance. When a database is started on a database server (regardless of the type of computer), Oracle allocates a memory area called the System Global Area (SGA) and starts one or more Oracle processes. This combination of the SGA and the Oracle processes is called an Oracle instance. The memory and processes of an instance manage the associated database's data efficiently and serve the one or multiple users of the database.
网络服务名：连接数据库网络描述的名字。其中包括通讯方式,IP地址等
主机字符串可以认为是网络服务名
全局数据库名:数据库区别其它数据库的名字,在域中的话,包含域名(如:sales.us.acme.com),sales是自己起的名字,us.acme.com是域名
访问的表空间是不是与登录名间的关系是建用户时定义的默认表空间
我可不可以用sql/plus连别人客户端起的网络服务名。还有Oracle实例是什么？
“可不可以用sql/plus连别人客户端起的网络服务名。”
这句是什么意思？
要在自己的机子上建立服务名，才可以用sql*plus连接数据库。
Every running Oracle database is associated with an Oracle instance. When a database is started on a database server (regardless of the type of computer), Oracle allocates a memory area called the System Global Area (SGA) and starts one or more Oracle processes. This combination of the SGA and the Oracle processes is called an Oracle instance. The memory and processes of an instance manage the associated database's data efficiently and serve the one or multiple users of the database.