Comments on: Partitioning 12c

By: Oracle Database 12c and its features… « musingdba

Oracle Database 12c and its features… « musingdba — Thu, 18 Oct 2012 19:21:17 +0000

[...] Jonathan Lewis – Indexing 12c and Partitioning 12c [...]

By: Tanel Poder

Tanel Poder — Fri, 05 Oct 2012 04:42:38 +0000

I remember the old DSI optimizer material saying that _optimizer_search_limit = 5 means that CBO will evaluate up to 5 factorial (120) join permutations which may include cartesian joins and from then onwards only non-cartesian join orders (up to optimizer_max_permutations) per query block.

By: Uwe Hesse

Uwe Hesse — Thu, 04 Oct 2012 14:54:50 +0000

Exactly: Good strategy if the customer has purchased the Partitioning Option anyway.

By: Indexing 12c « Oracle Scratchpad

Indexing 12c « Oracle Scratchpad — Thu, 04 Oct 2012 14:48:11 +0000

[...] little detail that Hermann Baer mentioned in his presentation yesterday was the ability to create multiple indexes with the same column definition – something which [...]

By: Jonathan Lewis

Jonathan Lewis — Thu, 04 Oct 2012 14:29:36 +0000

Uwe,

It’s also interesting to consider that if Oracle doesn’t make this a feature of non-partitioned tables you could always turn every (non-clustered)heap table into a single partition partitioned table simply so that you can move the partition online. Simply create an empty partitioned cloned of the original table, then exchange partitions. (Only suitable as a strategy if you have already paid for the partitioning option, of course.)

By: Uwe Hesse

Uwe Hesse — Thu, 04 Oct 2012 06:55:43 +0000

I would certainly agree that the ‘move online’ feature for partitions is a great improvement of Oracle Database 12c!

By: Pavol Babel

Pavol Babel — Wed, 03 Oct 2012 10:31:46 +0000

there were also many of them filed in testing phase :) but 8 after go to production… in 11.2.0.3. it is crazy, worst then microsoft I’m affraid

instead of fixing significant shared pool isues we have 12c here.

By: Timur Akhmadeev

Timur Akhmadeev — Wed, 03 Oct 2012 09:49:58 +0000

“Just 8 SRs” :-)

By: Pavol Babel

Pavol Babel — Wed, 03 Oct 2012 08:07:46 +0000

I like new features and some of partitioning enhacements seems to be usefull. However we will not upgrade to 12c sooner than in 4 years.
We have upgraded our largest databaese (corebanking system application, 4500 users) recently (9.2.0.8 -> 11.2.0.3). 11g has been relased 5 years ago (11gR2 3yeaes). I’ve filed with my colleague 8 SR! 4 of them have quite big negative impact on business

- very silly new SQL locking mechanism with FK on tables in RO tablespaces (introeuced in 10gr2, thank to God it is possible to switch it off)
- huge allocations in KGLH0 heaps and KKSSP even 11.2.0.3 (shared pool)
- many shared pool issues, BTW oracle was forced tu disable shared pool durations in 11.2.0.3 because of several bugs
- issue with select for update on table with FBI (also mentioned here on your blog)
- dataguard (max avsilability) issue, LNS process (primary) and RFS (standby) communication use to hang resulting into 30seconds “whole database commit hang” which is terrible for OLTP system. servers, disk subsystem and network are OK..
- index SS access path costed too low (index cost formula consider CLUF for index SS in same way as for index RS)
- flashback database dos not work with standby and TTS (unless tts are switched RO->RW->RO)

Regards
Pavol Babel

By: Noons

Noons — Wed, 03 Oct 2012 05:13:07 +0000

Hmmm…. Given the largest sections of the SQL manual already are by far the CREATE and ALTER TABLE ones, I shudder at the thought of what this is going to do to them…
Still: very cool stuff, indeed! And most welcome.