Re: ** HELP! a couple of "expert" questions **

Martin Malley wrote:
>
> > bpuett_at_interpath.com (Brad Puett) wrote:
> >

 <snip>
> >
> > >1) I KNOW that if you have the ORACLE_SID and ORACLE_HOME
> > > environment variables set correctly, you can log in and
> > > do things with SQL*Plus ... I ALSO KNOW that if you have
> > > the ORACLE_SID, you can find the corresponding ORACLE_HOME
> > > by looking in the /etc/oratab file ...
 

> > > What I don't understand is once you have both variables, HOW does
> > > Oracle determine where your data files are? I mean physically,
> > > not logically ... What I'm trying to do is prove that I'm working
> > > with the correct tables in SQL*Plus, but I only know ORACLE_HOME
> > > and ORACLE_SID ... I need to know which tables are "attached" to
> > > these 2 variables ... SOMEONE ELSE set up the tables (who is no
> > > longer with the company) and no one else there knows much about
> > > Oracle (they've only had it for 6 weeks!)

Oracle works differently than most of the the Other PC based databases. Oracle has to be up and running for you to access sql*plus and run any queries.
Oracle maintains all the information about everything in the data dictionary.
The tables in Oracle will belong to a schema. If you are logging in to the
schema then you can use user_tables, or all_tables to find out the tables
that this user has created or has access to. If you happen to have DBA privs, use dba_tables to find out all the tables for all the users in the database. It does not matter who setup these tables. As for the tables being attached to the env variables, they are not. The tables will belong to the Instance, which is running. By specifying the SID and HOME you are logging on to the instance. Also if the instance is not running you cannot log into oracle using sql*plus.

> >
> > >2) What do most people use to back up their data base files? Tar or export?
> > > I KNOW that you can use TAR to backup everything for the purposes
> > > of restoring all the data and structures ... suppose you just
> > >want a cum-
> > > lative backup, what do you use? Suppose you want to ensure that, once
> > > you've made changes to the structure of the database (i.e. you have to
> > > increase the storage size, change some keys in tables, etc.), you can
> > > restore the data back to the way it was (Note: I don't mean make any
> > > changes that would preclude putting the data back correctly [adding new
> > > fields, etc.])
 

> > >3) If you happen to be an "expert" in the software package "Pointman", I have
> > > some other questions (mostly in how it interacts with the
> > >database, etc. --
> > > nothing too technical!)
 

> > >Thanks for any info you can give me!!!
 

> > >--
> > >Brad Puett
> > >bpuett_at_interpath.com

<snip>
...

As for backups, get the book by Rama Velpuri called Backup and Recovery Handbook.

-- 
Regards,

Thotakura Kishore
Oracle Database Administrator
FORD Motor Co
Dearborn, MI.
e-mail:tkishore_at_ford.com
------------------------------------------------------
Views expressed are mine, and do not represent the 
views of Ford Motor Co.
------------------------------------------------------