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Home -> Community -> Mailing Lists -> Oracle-L -> Re: Partitions of table read only
Jack,
It is possible to have some partitions of a table
read only and some read write. Possible even if they are subpartitions. They are
requird, say, in a DW environment, where the current quarter's data is read
write but the rest are read only.
You can backup the read only tablespace only once,
and then <important> as long as you never make it read write
</important> you can recover it.
Since you are probably referring to a sort of
archival system, you can follow an approach I am using here. Our
requirement is to hold data online for three years, actually 12 quarters. So, in
the beginning of a quarter, I make the oldest partition of the tables a table
(alter table exchange partition) and make that tablespace read only. Then I
"transport" the tablespace to an optical jukebox using export/transportable, and
drop the tablespace. The tablespaces are named in a format with the year and
quarter in their names, so they are always unique. When the time comes to use
these older partitions, I simply plug them in and drop them after the rowrk is
done. This makes the process transparent to the user, actually to the tools used
by the user.
HTH.
Arup Nanda
<BLOCKQUOTE
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
Sent: Wednesday, June 18, 2003 10:49
AM
Subject: Partitions of table read
only
Hi,
I would like to know if it is possible and what the
pitfalls are if I do the following.
Partition a large table into partitions based on
date. Data is only entered and read and
never altered, so I would like to move older partitions to read only
tablespaces and possible read only devices so the backup will be made
quicker.
Is it possible to have parttions of the same table
spread across read only and read/write tablespaces? <FONT
face=Arial size=2>Am I correct in assuming that once you backup a read only
tablespace there is no need to backup the same again. (provided you don't make
it read/write add data and make it read only again).?
Does anybody have a procedure already that
automatically creates the new partitions let say every month?
TIA
Jacob A. van Zanen
Oracle DBA
Quant Systems Europe b.v.
Tel : +31 (0) 251 -
268 268 Mobile:
+31 (0) 6 51308813 <FONT face=Arial color=#0000ff
size=2>Fax: +31 (0) 251 - 268 269<FONT face=Arial color=#000080 size=2> <FONT face=Arial color=#000080 size=2>E-mail: <A href="mailto:[EMAIL PROTECTED]"><FONT face=Arial color=#0000ff size=2>[EMAIL PROTECTED]
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