Comments on: Query transformation – Part 1

By: Query transformation | BLOG DO ALEXANDRE PIRES "DBA"

Query transformation | BLOG DO ALEXANDRE PIRES "DBA" — Tue, 15 May 2012 23:30:55 +0000

[...] the concepts behind Query transformation. Some of the optimizations that we see here works from version 11gR1 onwards and so, these test cases might not work in the versions 10g and [...]

By: Programming

Programming — Thu, 03 Nov 2011 18:31:39 +0000

Programming…

[...]Query transformation – Part 1 « Oracle database internals by Riyaj[...]…

By: Log Buffer #188, a Carnival of the Vanities for DBAs | The Pythian Blog

Log Buffer #188, a Carnival of the Vanities for DBAs | The Pythian Blog — Mon, 10 May 2010 15:00:27 +0000

[...] Shamsudeen posts a detailed review of the different query transformation techniques the Oracle query optimizer may use on your [...]

By: laks

laks — Mon, 03 May 2010 04:31:33 +0000

Hi,
The trace file and associated trm file in 11.1.0.7.0 db seemed like any other normal trace in udump but for the huge size due to redo/buffer contents getting dumped inside.
There were no errors in alert log during that time.
The code executed didnt throw any errors however based on my understanding it does a lot of deletes.
i woudl revisit the code executed to get better idea,

thanks for your time
regards
laks

By: Chirpir News | Query transformation – Part 1 « Oracle database internals by Riyaj

Sun, 02 May 2010 16:10:33 +0000

[...] Read full story [...]

By: orainternals

orainternals — Sun, 02 May 2010 14:31:49 +0000

Hi
What is the trace file name? There is probably a process encountering exception or ASSERT. Any error messages in the alert log during the same time frame in any node?

Cheers
Riyaj

By: laks

laks — Sun, 02 May 2010 07:32:48 +0000

Hi,
A question though unrelated to your current posting.( I am sorry for this.)

I am seeing redo log contents getting dumped in a oracle 11.1.0.7.0 db when executing certain code.
As far as i know i couldnt see any settings/parameters causing this in the db.

The contents i see in a trace file that gets generated when executing the code are like this:

REDO RECORD – Thread:1 RBA: 0×000005.000d56d6.0010 LEN: 0×0070 VLD: 0×05
SCN: 0×0921.45464c21 SUBSCN: 1 05/02/2010 00:57:06
CHANGE #1 MEDIA RECOVERY MARKER SCN:0×0000.00000000 SEQ: 0 OP:17.3 ENC:0

REDO RECORD – Thread:1 RBA: 0×000005.000d570c.014c LEN: 0×0048 VLD: 0×01
SCN: 0×0921.45464c5e SUBSCN: 2 05/02/2010 00:57:22
CHANGE #1 MEDIA RECOVERY MARKER SCN:0×0000.00000000 SEQ: 0 OP:18.3 ENC:0
Reuse redo entry
Range reuse: tsn=1 base=251713673 nblks=1024
….

Basically redo dumping is happening and i can see some buffer cache contents also get dumped.
Please let me know what would cause this behaviour.

thanks