oracle sql tuning books

Label:Original: SQL Server Tuning Series basics (Parallel operations Summary)ObjectiveLast three articles we describe how to view query plans, as well as some of the commonly used join operators, Union operators optimization techniques.In this paper, we analyze the parallel operation of SQL Server, as a multi-core computer prevalent today,

Oracle 11g has made some improvements in optimization. Oracle automates the following optimization: Redo Logfile Sizing Advisor-this feature recommends Redo the optimal size of log files to avoid excessive disk I/O caused by frequent checkpoints. Automatic Checkpoint Tuning-Oracle database can now optimize checkp

optimization phase. If the difference between the two is very large, the actual performance statistics are stored as statistical information feedback, and the statement is also marked as re-optimized. When the statement is executed the next time, statistical feedback is used to select a more appropriate degree of parallelism (DOP).--Note:1) from the Oracle 11GR2 backwards, the parallel hint in the statement will cause the system to automatically sele

SQL Auto-tuning is an Oracle-brought tuning tool that provides solutions.This time I mainly introduce the following automatic SQL tuning tools: Automatic SQL

rows from BigTable2 in the above statement, so we have chosen a nested loop, Scan BigTable2 to get the data in turn.For Nested loop join operators, you can refer to my second article.We know that this is the number of loops on the outside, which means that there are 4 threads executing nested loops in parallel. If the threads of each line is 25 rows, the internal table will be executed.4*25=100 times.Then, after the nested scan gets the results, the next step is to summarize the results of each

Author: (US) Tony Andrews Translator: Chen Yong Yang Health Series name: Chapter Hua programmer library Publishing House: Machinery Industry Publishing House ISBN: 9787111425021 shelving time: -6-4 published on: July 4,: 16 webpage: 86 versions: 1-1 category: more about computers> DB2 SQL Performance Tuning tips computer books DB2

statement that will form a specific plan, and the resulting specific plan is not always optimal, which is related to the content distribution, the amount of data, the type of data in the database's existing data tables, and the statistics that are used to record these details.All optimal planning choices are based on existing statistical information, and if our statistics are not updated in a timely manner, then the optimal execution plan will not be the best, and sometimes the worst.Reference

at the statement level, the hint syntax is:/*+ bind_aware*/;Ø about outlines: In the scene of outlines existence, the ACS will fail whether the system level is enabled or the statement level is enabled through hint;6. Conclusion:New features of Oracle Database 11g The ACS feature provides an easy way to efficiently share SQL statement execution plans with bound variables. Because ACS produces a new executi

Preface In the past decade, Oracle has become one of the world's most professional databases. For IT experts, it is to ensure that their company's productivity is improved by leveraging the powerful features of oracle. One of the most effective methods is to use ORACLE optimization. It has a lot of parameters and technologies to improve the performance of your

filtering out unwanted records before group by. The following two queries return the same result but the second one is significantly faster.The code is as follows:Low efficiency:SELECT JOB, AVG (SAL)From EMP GROUP job has job = ' president ' and AVG (SAL) >xxxEfficient:SELECT JOB, AVG (SAL)From EMPWHERE JOB = ' President 'OR job = ' MANAGER ' GROUP JOB having and AVG (SAL) >xxx7, usually, if the statement can avoid the use of subqueries, as far as possible without sub-query.Because the overhead

In the past decade,OracleIt has become one of the most professional databases in the world. For IT experts, IT is to ensure that their company's productivity is improved by leveraging the powerful features of Oracle. One of the most effective methods isOracle Optimization. It has a lot of parameters and technologies to improve the performance of your Oracle database. The following describes how to optimize

Oracle's Optimizer:There are two types of optimizations for Oracle: The rule-based optimizer (Rbo/rule based optimizer) and the cost-based optimizer (Cbo/cost based optimizer).Sometimes, it indicates that there is an index, but the query process obviously does not use the relevant index, causing the query process to take a long time, the resource is huge, where is the problem? First, we want to determine what optimization mode the database is running

best to monitor the users who have no permission to delete the wrong table. Of course, do not use an account unless necessary !) You can use EXECsp_configure'defaulttraceenabled',0; RECONFIGUREWITHOVERRIDE; To disable the default trail. Black box tracking helps us diagnose database failures. We should also find it when searching sp_create_trace on MSDN. Then we can create a similar stored procedure to quickly create a black box tracking, to help us diagnose some exceptions! CREA

. Create_snapshot; We can also use the Dbms_workload_repository package to complete the baseline, the default settings and other operations.ADDM (Automatic Database diagnostic Monitor AWR)Oracle is an internal consulting system, can automatically complete the most database of some optimization recommendations, giveSQLThe optimization, the creation of the index, the collection of statistics and other suggestions.ADDM report Generation:Sqlplus>@?/rdbms/

the article you learn SQL language experience, or probation book feel, we will elect 3 readers to give "SQL optimization core ideas" 1, quickly actively participate in it! Event deadline: May 10, 2018 In the "async Community " Backstage reply " concern ", you can get free 2000 online video courses ; recommend friends follow the tips to get books link, fre

Oracle Database 10g Performance Tuning tips and techniques is recommended. For Oracle performance test, diagnosis, analysis, and optimization, see! Chapter 2 Basic index principles (beginner developer and beginner dBA). For Oracle index optimization, refer! Chapter 4 tuning