Relationship among database, tablespace and data file ?

Can anybody explain the differences and the relationship among database, tablespace and data file. Is there any logical or physical type of relationship exists ? any brief explanation will be appreciated. Thank you.

more ▼

asked Dec 22, 2009 at 11:35 AM in Default

avatar image

771 73 75 79

(comments are locked)
10|1200 characters needed characters left

1 answer: sort voted first

A recent Oracle database consists of at least two tablespaces, SYS and SYSAUX. Older versions only required SYS. It's usual to have more tablespaces, as it is bad practice to store user objects in SYS, and it is common to have separate TEMP and UNDO tablespaces.

Each tablespace consists of one or more datafiles (except TEMPORARY tablespaces, which use tempfiles). The tablespace is the logical storage structure used by DDL for storage allocation.

A datafile is a physical storage structure, which is usually a file on disk. (But could be a raw device, or on an ASM disk group).

more ▼

answered Dec 22, 2009 at 12:50 PM

avatar image

Andrew Mobbs
1.6k 3 5

What's an ASM disk group?

Dec 22, 2009 at 12:52 PM KillerDBA

ASM is Automatic Storage Management. It's an Oracle subsystem that manages storage directly, replacing the filesystem and logical volume manager. It can handle RAID, optimize data placement on disk, and Oracle claim it offers improved IO performance over letting the OS manage the storage. It also means DBAs don't need to talk to sysadmins as much, which can't be a bad thing :-). A disk group is the physical storage element within ASM. See http://download-uk.oracle.com/docs/cd/B28359_01/server.111/b31107/asmcon.htm for the documentation.

Dec 22, 2009 at 01:39 PM Andrew Mobbs

Thanks for the explanation.

Feb 08, 2010 at 12:28 PM KillerDBA
(comments are locked)
10|1200 characters needed characters left
Your answer
toggle preview:

Up to 2 attachments (including images) can be used with a maximum of 524.3 kB each and 1.0 MB total.

Follow this question

By Email:

Once you sign in you will be able to subscribe for any updates here



Answers and Comments

SQL Server Central

Need long-form SQL discussion? SQLserverCentral.com is the place.



asked: Dec 22, 2009 at 11:35 AM

Seen: 2202 times

Last Updated: Dec 22, 2009 at 11:35 AM

Copyright 2018 Redgate Software. Privacy Policy