MySQL

1MARIADB Query CacheThe data in the cache is in open source form, in the form of key-value pairs (k/v)Key: The hash value of the query statement;Value: Query result of query statement;The data in the cache is mainly through the comparison of the

First view MySQL related directory under Linux[Email protected]:~# whereis MySQLMysql:/usr/bin/mysql----MySQL Run path/etc/mysql/usr/lib/mysql-----MySQL Installation path/usr/bin/x11/mysql/usr/share/mysql/usr/share/man/man1/mysql.1.gzIn addition,

First, installation environment1. Operating system version: CentOS 7.52. mysql version: 5.7.22 (Community Edition)3. mysql installation package: mysql-5.7.22-linux-glibc2.12-x86_64.tar.gzSecond, installation steps1. Check if other versions of MySQL

The MySQL default MyISAM storage engine, does not support thing handling, and the InnoDB storage Engine provides transactional security with commit, rollback, and crash resiliency. But compared to the MyISAM storage engine, InnoDB writes are less

1) Installation DependentYum Search Libaio # Retrieving relevant informationYum Install Libaio # Installation Dependency Package2) Check if MySQL is installedYum List Installed | grep MySQLIf so, uninstall all first, the command is as follows:Yum-y

There is index (A,B,C)-the combined Index multi-field is ordered and is a complete btree index. The following criteria can be used on the combined index query: A>5 A=5 and B>6 A=5 and B=6 and c=7 A=5 and

Refer to "MySQL Technology insider"One, MySQL architecture and storage engine1. Database and database instanceDatabase: A collection of physical operating system files or other file components;DB instance: There are database background

MySQL indexing feature 1. Role of the Index Greatly accelerate the retrieval speed of data and increase the efficiency of query Reduce disk I/O costs Ensuring uniqueness of data records Enables faster execution of SQL

Pessimistic lock Introduction (encyclopedia):Pessimistic locking, as its name implies, is a conservative attitude to the data being modified by the outside world (including other transactions currently in the system, as well as transactions from

How do I get the self-increment ID to start from 1 after MySQL clears the table data? That is, how to rearrange auto_incrementUse the truncate command when emptying a table without the delete commandmysql> truncate test;Benefits of using the

Environment Description:Operating system: Red Hat Linux 6Installing the Mysql5.7 versionInstallation Instructions:First, prepare the MySQL installation packageSecond, prepare the installation environment.Operation Guide:One, download the MySQL

Sometimes when you use a script to insert data into MySQL, the insertion time is long because of the large amount of insertions. This time if you want to stop the insert operation, you can open MySQL Command line, enter:MySQL> show processlist;You

MySQL has many engines,MyISAM, InnoDB, MERGE, MEMORY (HEAP), BDB (BerkeleyDB), EXAMPLE, Federated... Wait a minuteMore commonly, InnoDB and MyISAM.. MyISAM does not support transactions, INNODB support, MyISAM does not have atomicity, and if you

When I landed on MySQL, there was this problem: Can ' t connect to local MySQL server through socket '/var/lib/mysql/mysql.sock ' (111)Workaround:1. Delete Mysql.sock FirstCd/var/lib/mysqlMV Mysql.sock Mysql.sock.bak2. Login

1. Why do I learn MySQL stored procedures?Because I did not understand the stored procedure before, did not find the bug in time, then spent one months to learn the MySQL stored procedure, the company all the stored procedures and all the tables are

In the project to do, you draw the area graph, and store it up, there is the need for updates, the storage file is not, think of the database now support the spatial database.MySQL is now used to continue to use MySQL to store and manage spatial

A brief introduction: we will continue to analyze binlog, but do not go into the codeTwo versions 5.6FormatGtid and traditional formatsTraditional formatOne binlog for specific transactions note-11 Update records the values of all columns before and

The index condition push (ICP) is an optimization of how MySQL uses an index to retrieve rows from a table. Without an ICP, the storage Engine traverses the index to find rows in the base table and returns them to the MySQL server, which evaluates

MySQL basic syntax:1. Create library: The name of the database;Create a library with encoded format: Create database name character set encoding format;Delete Library: drop database name;2. CREATE TABLE: Name of Creation table table (field 1 type 1,

I. Innodb_flush_log_at_trx_commitThis parameter name has a log, which is related to the log. Is the time to use to control the writing of data in the buffer (log buffer) to the log file, and the log file data flushing to disk (flush). The setting