performance tuning in oracle 11g

Tags: Oracle performance databaseWhen Oracle queries come with efficiency issues, we often need to understand the problem so that we can solve the problem. Oracle provides trace information for SQL execution, which contains textual information about SQL statements, some execution statistics, waiting during processing,

Example of Oracle full-text index performance advantages 1. Experiment description: Operating System: rhel 5.4x86 Database: Oracle 11g R2 Ii. Procedure: 2.1 create a t_btree table and create a B-Tree index. The index key is object_name: SQL> create table t_btree as select * from dba_objects; Table created. SQL> create

1,sql Types of ParseSQL Parse is usually divided into hard parsing and soft parsing, and when SQL is executed for the first time, hard parsing occurs, and then execution is performed if the shared pool Can be found in the soft analysis. Therefore, to improve the performance of the data, it is possible to have SQL executed every time found in the shared pool .Under what circumstances will the 2,sql send hard parsing?  1   ) Statistics Informa

With SPA, you can play a specific stream based on various types of changes (such as initialization parameter changes, optimizer statistics refresh, and database upgrades)SQL or the entire SQL load, and then generate a comparison report to help you evaluate their impact. In versions earlier than Oracle Database 11g, I must capture all SQL statements and trace and run these statements,Then get the execution p

step is to wait for the event: Event waited on Times waited Max. Wait Total waited ---------------------------------------------------------------------------------- sql*net message to client 502 0.00 0.00 sql*net Message from client 502 0.08 15.42 Sql*net more data to client 0.00 0.01Times waited: Waiting time takes timeMax. wait: The maximum wait time for a s

"Performance Tuning" Oracle AWR reporting metrics full resolution What is AWR? ===================================================================================================== AWR (Automatic workload Repository) A bunch of historical energy data, placed on the Sysaux table space, AWR and Sysaux are all 10g, are the key features of Oracle tuning; About

1. Types of SQL parse SQL parse is usually divided into hard parsing and soft parsing. When SQL is executed for the first time, hard parsing will occur, and subsequent execution will be soft parsing if it can be found in the shared pool. Therefore, to improve data performance, try to find the SQL statement executed each time in the shared pool. 2. Under what circumstances does SQL send hard parsing?  1) Changes in Statistics Zookeeper 2) ddl operati

and uses an optimal execution plan that returns all results as soon as possible. First_rows_n based on the CBO, returns the first n rows of data as soon as possible, and the value of n is 1,10,100,1000 First_rows a method based on the combination of CBO and heuristics to find the quickest way to return to a few previous rows; This parameter is primarily used for backwards compatibility. Rule uses a CBO-based optimization rule. The Oracle