sql tuning examples

SQL Server Performance Tuning methodology and common tools, SQL Server Tuning In earlier articles, we mentioned the DETECT methodology in Performance Tuning. Here we will briefly review the DETECT methodology. Discover the problem: found the problem Lead e the conditions: E

How to use Oracle's Dbms_sqltune package to execute SQL Tuning Advisor for SQL self-tuning1 ". Here is a simple example to illustrate the use of Dbms_sqltuneStart by running a SQL that you want to tune, and then get the SqlidSql> SELECT * from V$sqltext where sql_text like ' select * from dual% ';ADDRESS hash_value sql

Label:Original: SQL Server Tuning series advanced (How to index tuning)ObjectiveIn the previous article we analyzed the role of statistical information in the database, and we have learned how the database uses statistics to control the distribution of the contents of tables in the database. Children's shoes are not clear and can be clicked for reference.As a

How to use Oracle's Dbms_sqltune package to execute SQL Tuning Advisor for SQL self-tuning1 ". Here is a simple example to illustrate the use of Dbms_sqltuneStart by running a SQL that you want to tune, and then get the SqlidSql> SELECT * from V$sqltext where sql_text like ' select * from dual% ';ADDRESS hash_value sql

Common SQL Tuning Tips and SQL Tuning tuningtips Create an appropriate index (refer to correct database index creation) Replace OR with UNION (applicable to index columns) Replace in and not in with exist and not exist Do not declare numbers in character format (this will invalidate the index an

Oracle tuning uses related SQL, oracle tuning related SQL Select * from v $ session where username is not null;Select username, count (username) from v $ session where username is not null group by username;Select count (*) from v $ process;Select value from v $ parameter where name = 'processs ';Select count (*) from

Tags: style c tar ext a intHow to use Oracle's Dbms_sqltune package to run SQL Tuning Advisor for SQL automatic tuning1 ". Here's a simple example of how dbms_sqltune is used.First execute the next SQL that you want to tune, and then get the SqlidSql> SELECT * from V$sqltext where sql_text like ' select * from dual% ';

Tags: sdn is ola visible reason water personal tuning tunToday, while watching Tri Hua's SQL optimization book, he saw a case in which he solved the SQL performance problem, and Tri Hua the teacher successfully positioned the problem and solved it. Here, on the basis of Tri Hua teacher analysis and positioning, do further analysis and reasoning, so that we can st

Supports SQL tuning and SQL TUNING A friend of mine found me a few days ago and said that an SQL Performance problem exists to see if it can be optimized. The process is as follows: Snow Leopard 9:35:10 Are you there? Orchid island master 15:07:39 I forgot. What's the matter

inner table size is multiplied by the number of parallel service processes greater than the physical size.3) Pq_distribute (Tab_name, none,broadcast): This combination forces all data rows within the table to be broadcast to each consuming parallel query service process, while the outer data rows are randomly partitioned. This hint is recommended when the inner table is more than the outside hour. An important principle is that the none/broadcase hint is recommended when the inner table size is

:37YesOrchid Island Main 15:34:51Oh.Orchid Island Main 15:35:12Other, not quite understand your data in the situation, not very good fine optimization.Orchid Island Main 15:35:44Should still be quick.Snow Leopard 15:36:34GoodSnow Leopard 15:36:36Let me seeOrchid Island Main 15:37:16For example: The index of the other two tablesSnow Leopard 15:37:31WellOrchid Island Main 15:37:43The full table scan, although the table is small, but to 0.5s, should also be a small proportion.Snow Leopard 15:37:55I

Tags: establishing operations common Invalid database index characters NULL join exist Establish an appropriate index (refer to "pose for proper database indexing") Replace or with union (for indexed columns) Replace in, not exist with exist, not Do not declare numbers in character format (invalidates the index, resulting in a full table scan) Do not use SELECT * (List each column after select) Do not perform calculations in join and WHERE clauses (t

Tags: ATI latest sel Opening technical file reference tis onlineNow has been doing the project, the amount of data is relatively small, at the beginning of the time did not feel, because it is just beginning, the amount of data is very small, in the process of the use of speed is very fast, but with the constant growth of data volume, found that the program is more and more slow, even the problem of timeouts, so to the program Early project is relatively tight, not for the Big Data volume busine

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