Home » RDBMS Server » Performance Tuning » Oracle Compression Question (Oracle 10GR2)
Oracle Compression Question [message #318332] Tue, 06 May 2008 08:59 Go to next message
Triton46
Messages: 3
Registered: January 2008
Junior Member
OK, knowing that non-direct inserts going into a compressed table do not get compressed, what about the following scenario:

You have a table TAB_A that is made up of two partitions (LIST) based on an operational column COL_COMPR_YN. If COL_COMPR_YN = 'Y' then the data resides in partition PART_COMPR. If COL_COMP_YN = 'N' then the data reside in partition PART_NOCOMPR. PART_COMPR is a COMPRESS partition, PART_NOCOMPR is a NOCOMPRESS partition.

1)If I update a row in PART_NOCOMPR from COL_COMPR_YN = 'N' to 'Y', will the data get set to COMPRESS when moving into the partition (ROW MOVEMENT ENABLED) or would it act like a non-direct insert and leave the data as NOCOMPRESS?
Re: Oracle Compression Question [message #318345 is a reply to message #318332] Tue, 06 May 2008 09:27 Go to previous messageGo to next message
Michel Cadot
Messages: 64111
Registered: March 2007
Location: Nanterre, France, http://...
Senior Member
Account Moderator
It is a non direct operation, so row is not compressed.

Note: It will be in 11g.

Regards
Michel
Re: Oracle Compression Question [message #318362 is a reply to message #318332] Tue, 06 May 2008 10:17 Go to previous messageGo to next message
Triton46
Messages: 3
Registered: January 2008
Junior Member
Thanks, that was my assumption. Anyway to influence the "ROW MOVEMENT" to utilize a direct path?
Re: Oracle Compression Question [message #318369 is a reply to message #318362] Tue, 06 May 2008 10:56 Go to previous message
Michel Cadot
Messages: 64111
Registered: March 2007
Location: Nanterre, France, http://...
Senior Member
Account Moderator
No.

Regards
Michel
Previous Topic: How to tune a view using 3 big tables
Next Topic: Importance of index unique scan (cost=0)
Goto Forum:
  


Current Time: Mon Dec 05 21:37:21 CST 2016

Total time taken to generate the page: 0.06291 seconds