toad sql tuning

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

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

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

I. Preface Index plays an important role in database performance. The advantages and disadvantages of index design directly affect the efficiency of DB execution. Therefore, when performing DB tuning, some of them will start to process the index. SQL server also provides a good tool for Database Engine Tuning Advisor and provides some advice on index creation and

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

in 10g, Oracle launched its own SQL optimization aids : SQL Optimizer (SQL Tuning Advisor :STA) , it is the new Dbms_sqltune package. Use the STA to make sure that the optimizer is in CBO mode. but I think the use of such tools, only for the people who do not understand the tuning