toad sql tuning

Label:ObjectiveIn the previous article, we analyzed the usage of query hint as the first of the last play module of tuning series. Interested can click to view: SQL Server Tuning Series play turn (how to run with query hint (Hint) bootstrap statement)This article continues to play the contents of the module, the same, or want to grasp the previous series of conte

SQL Tuning Advisor:Create a taskDECLAREMy_task_name VARCHAR2 (30); My_sqltext CLOB; BEGIN my_sqltext: = ' SELECT/*+ ORDERED */* ' | | ' From Employees E, Locations L, departments d ' | | ' WHERE e.department_id = d.department_id and ' | | ' l.location_id = d.location_id and ' | | ' e.employee_id Running tasksBEG

statement | 471 | 43803 | 979 (1) | 00:00:12 || 1 | table access by index rowid | T1 | 1 | 9 | 2 (0) | 00:00:01 || 2 | nested loops | 471 | 43803 | 979 (1) | 00:00:12 || * 3 | table access full | T1 | 471 | 39564 | 36 (0) | 00:00:01 || * 4 | index range scan | T1_IDX | 1 | 1 (0) | 00:00:01 |Bytes --------------------------------------------------------------------------------------Predicate Information (identified by operation id ):---------------------------------------------------3-filter ("A

Original: SQL Server Tuning Series play turn three (use index hint (Hint) to boot statement maximum optimization run)ObjectiveThis article continues to play the content of the module, about the location of the index in SQL Server No need to say, this article will analyze how to use the Hint Bootstrap statement to fully use the index to run, as well as a solid gra

Label:Original: SQL Server Tuning Series advanced (in-depth profiling statistics)ObjectiveAfter the analysis of the previous few, in fact, in general has been the first glimpse of the importance of SQL Server statistics, so this article will be sacrificed this artifact.This content will be very long, sit good bench, melon seeds snacks and so on ...No nonsense, go

statistic changes more than 500. For a table with a data volume greater than 500 rows, when the first field data of the statistic changes more than the 20%* (total data volume of the table). So for larger tables, SQL Server recalculates the statistics only after more than 1/5 of the data has changed. 2, the temporary table can also have statistics information. This is one of the reasons why temporary table optimizations are used in many case

Original: SQL Server Tuning Series Basics (subquery operations Summary)ObjectiveIn the previous articles, we introduced a series of descriptions of operators and the optimization methods and techniques for each operator. This includes a series of our common operators, including how to view execution plans, how several datasets are commonly used, how to join operators, and parallel operators. Interested chil

N years ago, just when the contact with SQL, is a multi-table query in a variety of internal connections, external connections, left outer connection, right outside the connection of a variety of connections to get dizzy.What's more, there are two different ways to read the table connections in the book.For example, the query for table A, table B1, internal connection two kinds of wording:SELECT * from A, B where a.id = b.id;SELECT * from A join B on

SQL Server Tuning Series Article summary: This is a series of articles on SQL Server tuning, which basically covers the decomposition of the query operations we write in the day and the tuning content items, all original ... The first basic module focus on the basic content

Original: SQL Server Tuning Series Advanced (query statement running several indicator value monitoring)ObjectiveIn the previous article, we analyzed how the query optimizer works, including: detailed operation steps of the query optimizer, analysis of filter conditions, optimization of index items, and other information.In this article we analyze the detection of several key indicator values in the course

Label:Original: SQL Server Tuning series play Turn II (how to run with the aggregation joint hint (Hint) bootstrap statement)ObjectiveIn the previous article, we analyzed the usage of query hint as the first of the last play module of tuning series. Interested can click to view: SQL Server

Label:The main steps used by SQL Tunning Advisor: 1 Setting up Tunning task 2 Execute Task 3 showing tunning results 4 Follow the recommendations to run the corresponding tuning methodHere's how to do it in this order: 1 Setting up test tables and indexes Sql> CREATE TABLE test_sql_advisor as SELECT owner,object_name,object_id from Dba_objects;Table createdSql> S

Label: Objective About SQL Server Tuning series is a huge content system, not a word two words can be analyzed clearly, this article first in the SQL tuning in the most commonly used query plan to parse, to do a good job of the basic grasp, tamping basic skills! Then we talk about the overall statement

Original: 2-year summary of SQL Server DBA tuning2 years SQL Server DBA Summary of tuningWhen I was 2 DBA I felt that there was something that needed to be shared with everyone to discuss the book first.Book List1. "In-depth analysis of SQL Server 2008 series" This is the MSSQL 2005 Technology Insider series. Version 2012 also out of interest can see, Technical I

Label:Original: SQL Server Performance Tuning Training IntroductionHello everybody, this is the first blog post I wrote in the blogging park, and the reason I want to open this blog is a record of my interest in MS SQL Technology learning. As a computer professional graduates, their own grasp of the technology always feel very superficial, Bo and not specialized

threads.Of course, here are a few thread operations can set their own, the maximum recommended for the current system configuration of the logical core number, of course, the large set can be just useless.Second , index Hint hints (index Hint)The so-called index hint hint is to force the query optimizer to perform a scan of a query statement or use a specified index.In this way, we often use in the tuning of a way, many times we create the index is i

operation This is it, the next we add to SQL Server on the use of the index and dynamic index content, About indexes I believe that many people who understand database products are familiar with it, but the way in which some statements in SQL Server take advantage of the index may not be clear, our next analysis of this piece, to understand the indexing method and optimization techniques, interested in adv

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,

both are created in the SGA but SQL plan directives have not yet been persisted to the Sysaux table space, and statistical feedback is used during the re-optimization period, ignoring the existence of SQL plan directives.Ø both are created but the SQL plan directives are persisted to the Sysaux table space, and the SQL