oracle performance tuning books

Tags: Oracle performance optimization Oracle Optimization training Oracle Database Optimization Oracle Database Performance Tuning Oracle

that can be recovered. If you do not have a COMMIT transaction, Oracle restores the data to the state it was before it was deleted (exactly before the delete command was executed) and when the truncate is applied, the rollback segment no longer holds any recoverable information. When the command runs, The data cannot be restored. So very few resources are invoked and execution times are short. (Translator Press: truncate only in Delete full table app

The Oracle tutorial you are looking at is: Oracle SQL Performance Tuning Series Learning Ii. 4. Select the most efficient table name order (valid only in the Rule-based optimizer) The Oracle parser processes the table names in the FROM clause in Right-to-left order, so the

The Oracle tutorial being looked at is: Oracle SQL Performance Tuning series learning one. 1. Choose the appropriate Oracle OptimizerThere are 3 Oracle optimizer types:A. Rule (rule-based) b. Cost (based on costs) c. CHOOSE (optio

$02HISTORYALARM20140801USABLEIDX_HISTORYALARM$02HISTORYALARM20140802USABLEIDX_HISTORYALARM$02HISTORYALARM20140803USABLEIDX_HISTORYALARM$02HISTORYALARM20140804USABLEIDX_HISTORYALARM$02HISTORYALARM20140805USABLE...... You can see that the index of the partition HISTORYALARM20140731 has been marked as UNUSABLE.When an index is marked as unavailable, the optimizer ignores these indexes, and Oracle does not maintain these indexes when changing the table in

Tags: style blog http color using OS IO strongOne, automatic workload library (Automatic Workload Repository,awr)The Automated Workload library (Automatic Workload repository,awr) is a tool provided by Oracle Corporation. AWR can automatically collect, process, and save performance statistics, which are stored in memory and then saved in a database that can be displayed in a report or queried through a view

------------------------------------------------------------------------------------------Idx_ historyalarm$02historyalarm20140731unusableidx_historyalarm$02historyalarm20140801usableidx_historyalarm$ 02historyalarm20140802usableidx_historyalarm$02historyalarm20140803usableidx_historyalarm$ 02historyalarm20140804usableidx_historyalarm$02historyalarm20140805usable ...You can see that the index of the partition HISTORYALARM20140731 is already labeled unusable.When indexes are marked as unavailable

details of the table, according to the name of the detail table can generally understand its content, and feel that there is no need to thoroughly understand the details of the structure of the table. and different versions of Oracle have a corresponding change to the structure of these tables. All, here the structure of the table and the corresponding contents are omitted ... For example: You see Stats$sql_summary, you can certainly think of a SQ

of total CPU time. Us:user time Sy:system time Id:idle time NOTES Vmstat does not require special permissions. These reports are intended to help identify system bottlenecks. Linux Vmstat does not count itself as a run- Ning process. All Linux blocks are currently 1k, except for CD-ROM blocks which are 2k. FILES /proc/meminfo /proc/stat /proc/*/stat ALSO PS (1), Top (1), free (1) BUGS Does not tabulate the "block IO" Per Device or count the number of system calls.

For some current releases, three dynamic performance views are available for DBAs (Database Administrator, Database Administrator) and developers, namely V $ SQL, V $ SQLAREA, and V $ SQLTEXT.These views can be used to collect statistics about SQL command execution. In Oracle 10g and Release 2, the fourth dynamic performance view, V $ SQLSTATS, is added to facili

components in SGA. This is a new feature of 10 Gbit/s compared with 9i, which simplifies DBA's work. Oracle itself is becoming more and more intelligent and continues to grow. Many people worry that DBAs will not be unemployed. As software becomes more intelligent and simpler, DBA will be eliminated one day. Most people who hold this idea do not have a deep understanding of computers. When we continue to study deeply, we will find that our current le

Tags: list img Direct processing manager requires POS manual sed Take the training of Oracle recently, and make a study summary here. 1, Oracle Database tuning can not only expect to modify a few database parameters to have a clear effect, the problem is more in the application, educating developers to correctly use the database is a heavy task. 2,

. You can use this sql_id's ASH report to supplement the information given here。 The related object sql_id is a CAFV93454T4JV SQL statement. INSERT into t values (' M ', +, ' young ', ' TTT ') principle SQL spends only 0% of its database time on CPU, I/O, and cluster waits. Therefore, SQL tuning guidance does not apply to this scenario. Review your SQL performance data to find possible improvement

is around 95%. This ratio is relatively optimized. Install statspack SQL>connect/assysdbaSQL>@?/rdbms/admin/spcreate Uninstall SQL>connect/assysdbaSQL>@?/rdbms/admin/spdrop/*Timed_statistics = true before collecting information;Altersystemsettimed_statistics = true;*/ Collect information SQL>connectperfstat/perfstatSQL>executestatspack.snap; Automatic Collection SQL>connectperfstat/perfstatSQL>@?/rdbms/admin/spauto Delete automa

Some time ago, in Ali mother new room pressure test process used in the LR test Oracle, with the DBA (landlords) in Hangzhou netcom New computer room for 1000 users of the pressure simulation test. The entire stress test takes two days. The following are some of the experiences: 1 The stress test process found that some of the SQL scripts performed very slowly and were optimized. 2 The best concurrent testing, otherwise the service is basically no p

information on the use and performance of the main hardware components of the system, as well as the performance of the operating system itself. This information is critical for detecting potential resource consumption, such as CPU cycles and physical memory, as well as detecting poor performance of peripherals such as disk drives. Operating system statistics ar

introduced in Oracle7.0.1.2, with roughly 100 waiting events. This number is increased to approximately 150 in Oracle 8.0, with approximately 200 events in oracle8i and approximately 360 waiting events in oracle9i. There are two main categories of wait events, idle (idle) Wait events and non-idle (non-idle) wait events.Information about idle events and non-idle events is now available through Google and can be found in much more detail, whileThere is

Preface In a single application environment or system with relatively simple business, the bottleneck of system performance problems is often self-evident. The premise for solving the problem is that locating the problem is easier to solve, however, in a complex application environment, various application systems tend to share and compete with system resources, and application systems may also have symbiotic or restrictive relationships, the balance

With the SPA, you can play specific types of changes depending on the type of change (such as initialization of change, optimizer statistics refresh, and database upgrade)SQL or the entire SQL payload, and then generate a comparison report that helps you evaluate their impact.In the version number prior to Oracle Database 11g, I had to capture all the SQL statements and execute them by tracing,Then get the run plan-this is a very time-consuming and er