oracle performance tuning tutorial

Third, index4. The cost of the indexThe previous sections describe the power of indexes to improve performance and how to use indexes, but indexes are also expensive1) Consume disk spaceAs mentioned earlier, indexes are cost-represented after an index is added. ibd Files (InnoDB engines) or. myi files (MyISAM engines) can become larger.2) causes DML operations to become slowerWhen you add an index, it is faster because the table sorts the data accordi

Tags: extracting day workload operation Dictionary sysdate requires module logic operationIn most cases, Oracle uses index t to traverse tables more quickly, and the optimizer improves performance primarily based on defined indexes. However, if the SQL code written in the WHERE clause of the SQL statement is not reasonable, it will cause the optimizer to delete the index and use a full table scan, which is

read times. The ways to refine each statement are:Check Optimizer statistics，Check the interpretation plan for the most efficient access pathMeasuringtry to replace SQL constructs, and test for possible new indexes, manifested views, and partitions. Test the performance of the entire application using the optimized SQL statement. Is overall performance improved? The method is reliable, but somewhat dilator

issues at every step of the environment creation. When creating a database, you also need to consider the functionality that affects maintainability. Databases that are easy to maintain can run normally for a longer time, which is also an important part of the overall performance. The create database statement in the "solution" section also takes into account the following maintainability features. Create an automatic UNDO tablespace (automatic UNDO

from pfile= '/home/oracle/init0321.ora '; --Create SPFile--reboot below (by default, SPFile is used)sql> shutdown immediate;Database closed.Database dismounted.ORACLE instance shut down.Sql> startup;Note:Pfile and SPFile default location:SPFile ${oracle_install_path}/product/11.2.0/dbhome_1/dbs/spfileorcl.oraIf the parameter does not specify a pfile location, the following file is used by defaultPfile ${oracle_install_path}/product/11.2.0/dbhome_1/db

TablesA table describes an entity such as employees. You define a table with a table name, such as employees, and set of columns. In general, you give each column a name, a data type, and a width when you create the table.1. Ordinary heap table (heap-organized Tables)For all scenarios, applications with specific scenarios have a performance bottleneck, and alternative types of tables need to be replaced depending on the scenario.2. Global temp Table (

Tags: merging RDBMS LTE data file nbsp Select line div2016-11-22Subquery: Scalar subquery inline view (In-line views) semi-join/reverse-connect scalar subquery Select followed by subquery similar to a custom function to overwrite an inline view (In-line view) from followed by a subquery similar to Design view sub-query A condom query is a garbage design that can cause performance problems. A semi-connection is a subquery that has a in/exists in the ba

screenshot of the page loading process. That's good. Now, you can: Switch your network speed (remember, not everyone has an ultra-fast internet) View Slide View Change the script to asynchronous (or make other adjustments) Compare slides You can adjust the speed in the DevTools. Another tool is Speedcurve, which I recently stumbled on. It was developed by two clever guys: Mark Zeman and Steve souders, and it looked very helpful. 5DevTools is excellent, how can we better understand its usag

Oracle Performance Diagnosis art (milestone book on Oracle Database optimization) [Original book name] troubleshooting Oracle Performance[Original Publishing House] apress[Author] (Swiss) Christian antognini [same as the author's work] [Translator's introduction][Translated

the hard disks. 6. Adjust operating system parameters such as the Oracle database running on UNIX operating systems, you can adjust the size of the UNIX data buffer, the size of the memory that each process can use, and so on. In fact, the database optimization measures mentioned above are interrelated. Oracle database performance degradation is basically the us

Database tool sysbench installation tutorial and performance test example, sysbench performance test Sysbench is a modular, cross-platform, multi-thread benchmark testing tool used to evaluate the database load of different system parameters. For details about this project, see: http://sysbench.sourceforge.net. It mainly includes the following testing methods:1.

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 th

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-bas

Oracle Cluster Concepts and principles (ii) Overview: write down the original intent and motivation of this document, derived from the Oracle Basic operating Manual of the previous article. The Oracle Basic Operations Manual is a summary of the author's vacation on Oracle's foundational knowledge learning. Then form a summary of the system, a review rev

Anything can have a positive impact on Oracle performance, such as changing the Oracle initialization parameters, adjusting the corresponding SQL, etc. the problem with Oracle's instance tuning is that overloaded Oracle's SGA can cause serious performance problems. Adjustme

provide 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 stati

LoadRunner monitors OracleHttp://www.docin.com/p-92077154.html HP performance monitoring best practices-database resource monitoring-Oracle monitoring Oracle Database Performance Tuning FAQHttp://www.orafaq.com/wiki/Oracle_database_Performance_Tuning_FAQ

identifies the session process ID of all users with the name starting with a: 1.select S.username, p.spid from V$session S, v$process P 2. 3.where s.paddr = p.addr and s.username like ' a% '; 4. 6) to sysdba into Sqlplus execution 1.alter session Set Timed_statistics=true; 2. 3.alter session Set max_dump_file_size=unlimited; 4. 5.oradebug Setospid 6. 7.oradebug Unlimit 8. 9.oradebug event 10046 Trace name forever, Level X/* Where x = (1,4,8,12) * * 10. 7 Track a session applicat

Importance of oracle data dictionary and dynamic performance table: because the data dictionary contains user information, we need to query the data dictionary when logging on and have permission information, we also need to query the data dictionary when performing operations, and we also need to query the data dictionary when operating data with constraints. Therefore, the data dictionary is very importan

software, testing the effectiveness of tuningChongqing si Zhuang Oracle Database performance Optimization 10 OCM expert teamHttp://www.cqsztech.com/content/109/227.htmlChongqing si Zhuang Technology Co., Ltd. is the Oracle third-party technical service units, southwest China is the earliest professional provider of Oracle