advanced oracle sql tuning

Tags: tabs Other applications ABS SSE contains increased data process structure understandingThe parameters of the tuning function in the Oracle database system are called initialization parameters, and the database administrator needs to properly adjust these initialization parameters to optimize the Oracle system according to the actual situation.1 introduction

. The customer provided an AWR report during peak hours. After careful analysis, it was found that it was a high-CPU-consuming SQL statement, which only took 85% of the CPU, this gives us an in-depth understanding of SQL optimization. We have also done some DB optimization before, basically through analysis tables, index creation, parameter adjustment, PATCH, and so on. However, this time, it lasted for a w

Kernel.shmmaxKernel.shmmax = 2147483648[Email protected] ~]# sysctl-p[Email protected] ~]# su-oracle[Email protected] ~]$ sqlplus '/as sysdba 'Sql*plus:release 10.2.0.1.0-production on Mon Nov 16 05:50:00 2009Copyright (c) 1982, 2005, Oracle. All rights reserved.Connected to:Oracle Database 10g Enterprise Edition Release 10.2.0.1.0-productionWith the partitionin

Io is very relevant, when the free buffer waiting in the v$session_wait of the entry is very small or not, Explain the DBWR process of your system will be enough, do not need to adjust, there are many items of free buffer wait, your system must feel very slow, then your DBWR is not enough, the resulting wio has become your database performance bottlenecks, the solution is as follows: A.1 to increase the write process while adjusting the db_block_lru_latches parameters Example: Modify or add the

the deterioration of performance is a variety of factors, and sometimes the results of the performance degradation caused by multiple elements, this requires the database administrator has a more comprehensive computer knowledge, can be sensitive to the impact of the database performance of the main reason. In addition, good database management tools are also important for optimizing database performance. Database performance optimization tools commonly used in

Document directory Preliminary steps Using bind variables There are several relatively easy steps you can take to improve performance. From the user's perspective, one of the most frequently used interfaces with a database involves SQL statements, so getting a handle on them is a good place to start, in terms of being able to see an immediate improvement. -->Oracle

of disk sorting will be greatly increased. This is mainly because at the end of the month, users will make statistics on the transaction data for the month. So at the beginning of the month, because of the number of transactions, so there will be more disk sorting occurs. In this case, it is necessary for the database administrator to adjust the relevant parameters. However, this adjustment is a temporary adjustment, until the cycle has passed, still need to transfer the parameters back. Only i

. server.2005. Technical Insider "series Conclusion This article first to this bar, short, easy to understand, this article mainly introduces the query plan of the joint operators, the next we analyze SQL Server parallel operations, in multicore hyper-threading gathered today, see SQL How server uses parallel operations to maximize the use of existing hardware resources to improve performance, is inte

It is troublesome to optimize an SQL statement before Oracle 10 Gb. However, the SQL Tuning Advisor tool launched in Oracle 10 Gb can greatly reduce the workload of SQL optimization, however, to use

Oracle _ advanced subquery, oracle _ advanced subqueryZookeeper Oracle _ advanced subquery ① SubqueryA subquery is another SELECT statement nested in an SQL statement.Subquery (internal

Tag: Time Condition number column arch OSI user CTE codeIn section 1.5 of the SQL Tuning Basics Overview 05-oracle Index Type and introduction, several "Common index execution plans" are mentioned: Index full Scan: Fully scanned indexes, block read, orderedIndex range Scan: Range sweep of indexIndex fast full Scan: Fast all scans of indexes, multiple rea

SQL Server Performance Tuning 3 (Index) MaintenanceHeat1 reviews Brook Stream GrassSQL Server Performance Tuning 3 (Index) MaintenanceObjectiveThe previous article describes how to improve the query performance of a database by building an index, which is really just the beginning. Subsequent to the lack of proper maintenance, the index you created earlier can e

Buy Oracle Database Course package and enjoy 85 discount!!Package Address: http://edu.51cto.com/pack/view/id-807.htmlPerformance optimization for Oracle 11g R2 databaseDatabase performance problem is the most discussed topic in database field, because it involves database principle, IO storage, server performance, foreground application and so on, so the performance problem is very test the optimization of

Oracle Adjusts Oracle's competition One of the benefits of Oracle is that it manages the free space in each table space. Oracle handles the space management of tables and indexes so that we don't have to understand the internal workings of Oracle's tables and indexes. However, for an experienced Oracle