[Q][023]create table

显示全部楼层 · 2005-2-28 12:57:00

When creating a table, you must place the table in which tablespace?
A One that holds temporary segments.
B One that has no rollback segments in it.
C One that hold the indexes of the table.
D One together with other tables of the same user.
Answer: D
为什么B不对？

千问 · 2005-2-28 12:57:00

B只是没有回滚段在的表空间，临时表空间里面也是没有回滚段的。不应该把表建立到临时表空间上。

千问 · 2005-2-28 12:57:00

Oracle中任何数据库对象如表等，都是给某个人的，或者说schema。
这样如果用户accA自己建立一个表，那么这个表必须放在acca所有的表空间中
换而言之，Oracle以用户为单位组织各种schema.
所以选D。
其实在OEM中也可以看到，其方案下都是一个一个如HR, SCOTT，这都是一个一个得Oracle
(用户，初学者一般很容易搞晕，不知道什么东西

)

千问 · 2005-2-28 12:57:00

In the real world, let us say we want to add a table to the database. Who shouldbe the owner of the table? IT workers come and go all the time. If the table owner is the owner who create it, we have a problem. When the guy leaves the company, are we going to delete this guy from the database? What do we do with the tables (and other objects) he owns?
I do not see 'schema' is a good idea. I think all objects in the database should be owned by DBA, not DBA per se, but DBA in general, as a DBA can come and go as well.