Re: Beginners in Oracle; Need some advice!
Date: 1996/08/24
Message-ID: <4vnpcd$74o_at_mtinsc01-mgt.ops.worldnet.att.net>#1/1
Mirwais Qader <mq_at_wohl.slh.wisc.edu> wrote:
>We have recently purchased an Oracle System and are in the process of setting it up, however,
>there are some things that I am not fully clear on.
>
>
>1. How many Instances (SID's I assume) can I run? We have one HP9000 server (UNIX 9.04): I
> would think only 1!
You can theoredically have as many instances as your resources can support.
>
>2. Is an instance the same as a database?
No an instance is specifically the SGA and Background processes (memory)
Segments are logical objects that take up space (ie table - data segment). a segment can not cross tablespaces
>
>4. If we have a production DB and would like to do development and testing, then I assume that
> separate DB's would have to be created: 1=production, 2=testing (?) Is this right? OR am I
> supposed to create a segment for the tables that are to be tested on and then drop that
> segment when the applications are in production???
A production and test database would be fine. Without getting into to much detail here you could have 1 database that has a test and production schema, again there are pros and cons do doing this also.
>
>5. I am a little puzzled about extents too. How do MAX and NEXT extents work?
Your INITIAL extent assigns this amount of space to the segment upon creation. As more space is needed, as the object grows(updates, inserts) it grows by the NEXT extent allocation. MAXEXTENTS is the maximum growth allowed.
> Am I correct in thinking that I have to "export" the database every month or so to tape to
> "defragment" the DB?
If your databse needs "DEFRAGED" EXPORT/IMPORT is an excellent way to do this.
>
>6. What are the different users and how are they different from the users I create? Is there
> groups of users that can be created like DBA's, USERS, DEVELOPERS, then under these the
> individual people?
>
> SYSTEM
> SYS
> SYSOPER
> SYSDBA
> Joe
> Mike
>
> What is the "oper" group that I created on UNIX for?
>
> When we create applications, does it have to be distributed to each user's "directory" or it
> can just be put on the server and those that have permissions to it (through groups or
> whatever) can then use it?
>
> Does each user get assigned to a particular rollback or redo log to reduce congestion?
Users accounts are required to access the database. Privileges incorporate additional levels of security allowing users to perform certain operations or perform certain operations against specific "objects" (tables, views, applications). Users are not assigned to rollback segments or redo logs.
>7. If I have around 40 tables, how may I distribute these?
>
> CUSTOMER_SERVICE segment 8 tables
> INDEX segment 6 "
> QUALITY CONTROL segment 5 '
> TESTING segment any tables that are being used for development
> INVENTORY AND SUPPLY segment
> TEMP segment
> etc..... [Does this logic make sense?]
>
>
> OR
>
> Put all 40 tables in 1 place?
>
>Any Help would be appreciated! I think getting used to the terminology is the hardest part.
Your a little confused on segments. Objects are segments for the most part. As far as configuring your database I could spend all day giving you different options, You need to consider as part of your configuration those things noit associated with Oracle that are contending for resources also.
DB Configuration
DATABASE
TablespaceA TablespaceB TablespaceC
TableA TableB IndexA TableC IndexB
SegmentA SegmentB SegmentC SegmentD SegmentE
Extent1 Extent1 Extent1 Extent1 Extent1
Extent2 Extent2 Extent2
Extent3
Extent4
Hope this Helps
R2
Independent Oracle Consultant - I am available
Received on Sat Aug 24 1996 - 00:00:00 CEST