By Jonathan Lewis
If you could have suffered the disappointment of staring at the optimizer do anything thoroughly extraordinary whilst the easiest execution plan is completely seen, or spent hours or days attempting to make the optimizer do what you will want it to do, then this is often the ebook you wish. you will come to grasp how the optimizer thinks, comprehend why it makes error, and realize the knowledge styles that make it move awry. With this knowledge at your fingertips, you are going to keep an immense period of time on designing and trouble-shooting your SQL.
Read or Download Cost-Based Oracle Fundamentals PDF
Similar oracle books
* strengthen carrier and message-oriented suggestions at the Oracle provider Bus following most sensible practices utilizing this e-book and ebook
* expand your functional wisdom of establishing suggestions at the Oracle carrier Bus
* filled with hands-on cookbook recipes, with the entire and entire resolution as an OSB and SOA Suite undertaking, made on hand electronically for download
Grasp Oracle E-Business Suite's Oracle common Ledger continue a centralized, hugely computerized processing platform across a totally built-in set of Oracle E-Business Suite functions utilizing Oracle common Ledger. This Oracle Press consultant explains the right way to make the most of Oracle common Ledger to distribute well timed and exact monetary details enterprise-wide.
Oracle Exadata Recipes takes an example-based, problem/solution method in displaying easy methods to measurement, set up, configure, deal with, computer screen, optimize, and migrate Oracle database workloads on and to the Oracle Exadata Database computing device. no matter if you’re an Oracle Database administrator, Unix/Linux administrator, garage administrator, community administrator, or Oracle developer, Oracle Exadata Recipes offers potent and confirmed suggestions to complete a large choice of projects at the Exadata Database desktop.
Seasoned Oracle Fusion functions is your one-stop resource for support with fitting Oracle's Fusion purposes suite on your on-premise surroundings. It additionally aids within the tracking and ongoing management of your Fusion surroundings. writer Tushar Thakker is well known for his writings and services on Oracle Fusion purposes, and now he brings his collected knowledge to you within the kind of this handy guide.
- Oracle Coherence 3.5
- Oracle Hacker's Handbook: Hacking and Defending Oracle
- Cost-Based Oracle Fundamentals
- Oracle Core - Essential Internals for DBAs, Devels.
- RMAN Recipes for Oracle Database 12c
Extra info for Cost-Based Oracle Fundamentals
REPORTING CPUSPEED Although the manual indicates that the cpuspeed is reported in cycles per second, there are two possible errors in the statement. , CPU speed in MHz). Even then, the number always seems to fall short of expectations—in my case by a factor of anything between 5 and 30 on various machines I’ve tested. The more subtle error then is that the value may actually be a measure of millions of standardized oracle operations per second, where a “standardized oracle operation” is some special subroutine designed to burn CPU.
As you can see, the Oracle kernel code has been extended to become more aware of the environment that it is running in, which should make it better able to produce the most appropriate execution plan for the moment that the query is optimized. Once you’ve worked through all four variations that Oracle has to offer, you might think you know all there is to know about the different methods of calculating the costs of a tablescan. But you’ve only just begun—remember that an index fast full scan is really just a variant on the tablescan idea; think about the fact that there may be some anomalies introduced by automatic segment space management (ASSM); and consider that tablescans can be performed using parallel execution, and might involve partitioned tables.
000000 blocks MAXTHR: 13938448 bytes/sec SLAVETHR: 244736 bytes/sec Of course, the CPUSPEED is just a number, and the optimizer is just doing arithmetic with that number, whatever it represents—but if you have a proper understanding of where the number comes from, you may be a little more cautious about fiddling with it. So how does the optimizer use these statistics? sql in the online code suite). Autotrace reported the cost of the query as 5,031 in the first three cases. Unfortunately, the cost in the case of the 32-block read size was 5,032, a small but unexpected variation.