MySQL

The idea of ①mysql optimization1,sql statement optimization and index optimization2, Optimization of database table structure3, System Configuration4, hardware optimizationIiView slow query log status: Show variables like ' Slow_query_log 'If the

MARIADB database management System is a branch of MySQL, mainly by the open source community in the maintenance, the use of GPL license. One of the reasons for developing this branch is that after Oracle acquired MySQL, there is a potential risk of

--Functions, stored proceduresSelect Definer from mysql.proc;update mysql.proc set definer= ' [Email protected]% '; --timed Event select Definer from MySQL. Events;update MySQL. EVENTS set definer= ' [Email protected]% '; --View Select Definer from

After downloading the free install version of MySQL, compress the package. At this point MySQL is not working yet and we need to do some work:1. Installing the MySQL ServiceCreate a new batch file, Startmysql.bat, with the following file

When I recently used thinkphp to find an error message that could not capture MySQL, such as inserting a primary key duplicate data into a table, the program is stuck on that statement as follows :( SQLSTATE[23000]: Integrity constraint violation:106

One, the concept of partitioningPartitioning allows multiple parts of a single table to be allocated across the file system according to the specified rules. Different parts of the table are stored as separate tables in different

There are many ways to introduce online.Step 1:Usegeneratedkeys, Keyproperty these two properties keyproperty the value corresponding to the primary key attribute in JavaBean---Parametertype=

--//storage functions, custom functions------------NewCREATE FUNCTION function_name (argument list) RETURNS return value typefunction Body-the function name, which should be a valid identifier, and should not conflict with an existing keyword. -a

MySQL multi-instance routine, there are mainly two kinds of programs can be achieved, these two kinds of programs have pros and cons, as follows:1, based on multi-configuration filesMultiple instances are implemented by using multiple configuration

Installation reference: Http://www.cnblogs.com/xiaoluo501395377/archive/2013/04/07/3003278.html, very detailed.After the installation is successful, the configuration must be configured to access MySQL from another machine:1. Open MySQL Access port 3

Log in to the root user and log in to the console with the root user.Use Mysqluse Mysql,mysql is a database created automatically by the MySQL database.Modify the data of the user tableUpdate user set Password=password (' 1234 ') where user= ' root '

Definition and usageThe Date_format () function is used to display date/time data in different formats. GrammarDate_format (Date,format) The date parameter is a valid day. format Specifies the date/time in which the output is formatted. Detailed

/*Name explanationSql_cache query Results cached (valid when query_cache_type=demand)Sql_no_cache query results are not stored in cacheQuery_cache_size indicates the size of the cacheQuery_cache_type Query Cache session type (0=off close query cache

At present, the more popular sub-table is twice times the expansion.Table A (ID, name, age, Sex)Based on the self-increment ID sub-table, through the trigger to synchronize the A to B, the program through the MoD 2 operation data, and then drop the

This paper summarizes the operation of index in MySQL, mainly involves the view, increment and deletion of index.1. View IndexHttp://dev.mysql.com/doc/refman/5.7/en/show-index.htmlSHOW {INDEX| | KEYS} {from| inch [{from | in} db_name[WHERE expr]2.

①. The most basic SQL statementSELECTFROM 表名 LIMIT 开始位置，显示条数②. The simplest page-paging logic1. Incoming page numbers$page$_GET[‘p‘];2. Incoming data based on page numbers$host="localhost";$username="Root";$password="";$db="Test";//Connect

The principle of MySQL deleting duplicate records is:After placing the column to be compared to group by, remove the minimum value of the primary key, and then delete the row that is not in the primary key of the temporary tableThe command line

MySQL installation compilationA cmake-3.0.2 compilationYum Install gcc-c++Yum Install Ncurses-develTar XF cmake-3.0.2.tar.gzCD cmake-3.0.2./configure--prefix=/usr/local/cmake3.0.2 && make && make installVi/etc/profile//Modify environment

We sometimes need to look at the execution history of MySQL, such as when we do SQL optimization, at least to know what SQL is executed, the framework will generally help us to assemble SQL, so in the program will not be able to print out SQL, this

MySQL Schema Optimization:1. Ensure the cleanliness of your database.2. Archive old data-delete extra rows retrieved or returned from the query3. Add an index to the data.4, do not overuse the index, evaluate your query.5. Compress text and BLOB