oracle query optimization tool

to improve the efficiency of SQL query how to write the precedence of where statement conditionshttp://blog.csdn.net/sforiz/article/details/5345359We have to do not only write SQL, but also to write good performance of SQL statements.(1) Select the most efficient table name order (valid only in the rule-based optimizer):The Oracle parser processes the table names in the FROM clause in a right-to-left order,

2014-06-25 BaoxinjianI. Summary SQL Trace is an Oracle-provided means for SQL tracing and is a powerful auxiliary diagnostic tool. SQL Trace is a very common method in the diagnosis and resolution of daily database problems.In general, a single trace can be divided into the following steps:1. Define the range of targets that need to be tracked and enable the required traces using the appropriate comma

Use of mysqlsla, a log tool for slow database query, which is more powerful than mysqldumpslow. Install mysqlslaSource code path: https://github.com/daniel-nichter/hackmysql.comSource code storage path:/usr/local/src1. Get source codeIf you do not have the git command, install git first.Yum install git Cd/usr/local/src Git clone https://github.com/daniel-nichter/hackmysql.com.git Cp-Rf hackmysql.com/opt/mys

protocol modules. This is only a protocol flow log table, and there are other tables. Nor can we set all the fields required for condition-making as indexes, so the index table will be about the same as the original table, and the index will be meaningless. Optimization on the database itself, I can't think of a good way to think about it at once. I feel that there is a large amount of data, even if there is no magic way in

the merge do not contain duplicate data, use Union all, as shown below:Select * From test_union1Union allSelect * From test_union2 There are two basic rules for query result sets using union: 1. The columns and columns in all queries must be in the same order. 2. Data type must be compatible Database Query Optimization: 1. To optimize the

In the optimization query, database applications (such as MySQL) mean the operation and use of the tool. Using indexes, using explain to analyze and query, and adjusting the internal configuration of MySQL can optimize the query. Any database programmer has the following exp

Oracle SQL optimization rules: Use the in operator as few as possible. Basically, all in operators can be replaced by exists. The SQL statements written in are easier to write and understand, but the SQL statements written in always have low performance, the steps executed by Oracle are used to analyze the differences between SQL statements using in and SQL sta

tables (the customer asked us to keep at least three months of records ). Index creation can play a certain role, but it still cannot solve our problem. Creating a physical table can no longer shorten the time, because one table is created every day, and 91 ~ 92 tables, more than 2700 for 30 protocol modules. This is only a protocol flow log table, and there are other tables. Nor can we set all the fields required for condition-making as indexes, so the index table will be about the same as the

default--that is, not included.DB: The log of which library to process.Top: Indicates how many first bars are sorted by rule.Sort: sorted by a rule, T_sum: sorted by total time, C_sum: sorted by total number of times, c_sum_p:sql statement execution count as a percentage of total executions. #开启慢查询日志项配置 Reference files optimized configuration of MySQL performance optimization my.cnf file: http://www.cnblogs.com/NiceTime/p/6848132.html Slow_query_log_

For the purchase of advertising site webmaster, in fact, most of the stationmaster is with can give their own website to bring certain traffic, although sometimes not much, but better than none. And the ultimate goal of the purchase link is also to improve the ranking to get more traffic. So, traffic is the ultimate destination of the website. It is really useful to analyze the site's overall situation from the site's traffic. And a lot of adsense in the buy ads, are particularly concerned about

... ########################################### [100%]1:mysql-administrator ########################################### [100%][Email protected] mysql]#Continue to install Mysql-query-browser, the beginning of the package[Email protected] mysql]# RPM-IVH mysql-query-browser-5.0r12-1rhel4.i386.rpmPreparing ... ########################################### [100%]1:mysql-que