MySQL

[[email protected] ~]# mysqldump-uroot-proot--DEFAULT-CHARACTER-SET=GBK test >/data/test.sql # Backup Test Library [[email protected] ~]# mysql-uroot-proot--DEFAULT-CHARACTER-SET=GBK test # recover Test Library[[email protected] ~]#

MySQL Database-indexIndex is a data structure in the database that is designed to help users quickly query data. Similar to a directory in a dictionary, you can find the contents of the dictionary based on the directory to locate the data, and then

MySQL Paging keywords:　　 limit m,n--m: Indicates the line from which to start, N: Query how many barsOracle Paging Keyword:: rownum SQL Server:top(under 2005 versions) 　　　　　 row_number ()(2005 later version)Query the first 10 data:SELECT * from 0

1.mysql Start ErrorWorkaround: See if the Basedir, DataDir, and other paths of the configuration files for the relevant path are correct.Resolution: See if there are files in the error path, if there is no file to find the corresponding soft link,

MyISAMthe default database engine before Mysql5.5 is most commonly used. High insertion, query speed, but no transaction supportInnoDBthe preferred engine for transactional databases, supporting ACID transactions, support row-level locking , MySQL 5.

What is an index: The index is a table of contents, and you can quickly locate the query data by looking at the index location in the catalog before finding it. For the index, it is saved in an extra file. The index is made up of one or more columns

The default yum source for CentOS 7 is mariadb, not our usual MySQL.This article will show you how to install MySQL through yum. First download the Yum source rpm package Specific address in:http://repo.mysql.com/You can choose the

The first method: select Current_date;Mysql> Select Current_date as Systemtime;+------------+| Systemtime |+------------+| 2009-07-29 |+------------+Second method: Select Now ()Mysql> Select Now () as Systemtime;+---------------------+| Systemtime |+

Many times in order to test the database design is appropriate, to optimize the SQL statement, you need to insert a large number of data in the table, how to insert a large number of data is a problem.The first thing to think about is to write a

1. View the root user temporary random passwordAfter Yum installs MySQL, it cannot log in to the database with a blank password, as follows:1 [[email protected]123 mysql]# mysql-u root-p231045 (28000for'root'@'localhost' ( Using Password:no)After

Web development is the mainstream of distributed programming in the future, usually the web development involves dealing with the database, the client from the server-side reading is usually in the form of paging, page by page reading is both

1. Create databases and Users--Change Password ctrl+shift+c/r Add/Cancel CommentSET PASSWORD for [email protected]=password (' new password ');--Query all the databasesSHOW DATABASES;--Create a databaseCREATE DATABASE IF not EXISTS T11;--Delete

MySQL has a couple of features:1: Multi-lingual support2: Can be good portability3: Free Open source4: Efficient (multi-threading support, full utilization of CPU resources, very fast running)5: Large data query and storage support6: Easy to learn

SHOW DATABASES; Show all databasesSHOW TABLES; Show all tables under the current databaseCREATE DATABASE dbname; New DatabaseCREATE TABLE tbname (id BIGINT UNSIGNED, PRIMARY KEY (id)); To create a new table, you must have at least one column when

Installationsudo apt-get install mysql-server mysql-clientView installation Port conditionssudo netstat-tap | grep MySQLConfiguration file Locationsudo vim/etc/mysql/my.cnfTurn off services/etc/init.d/mysql Start/stopUnloading[Plain]View PlainCopy

1. Download the MySQL installation package to the specified file:For example, I extracted the contents of the downloaded MySQL zip into this file, the specific file content is as follows:My.ini needs to create its own, the contents are as follows:==3

1. Write operations in the transaction, four isolation levels, all add exclusive locks.2. Read operations in the transaction, the first three isolation levels, no lock, the last isolation level, will be a shared lock.3. The above write and read

Previous article I mentioned in the JSP page badThis article is about interface and code separation, can initially achieve two or three people to work together to complete a projectOkay, no more nonsense, go to the chase.This is four steps.First

How to Use the MySQL authorization command grant This example runs on MySQL 5.0 and later. The simple format of commands granted to users by MySQL is as follows:Grant permission on database objects to users   1. grant normal data users the right to

Xtrabackup backup principle, xtrabackup backupPercona XtraBackupWorking Principle Percona XtraBackupIt is a crash recovery function based on InnoDB. CopyInnoDBData files, causing internal inconsistency; but then it crashes and recovers the files,