MySQL

Core points of Knowledge:1. View definition2. Benefits of view: security, resource saving, simple operation, identity of data3. Basic operation of the viewI. Overview of the ViewA view is a virtual table whose contents are defined by a query.As with

Access MySQL URL: https://dev.mysql.com/　　　　　　　　　　　　Below you need to log in to your Oracle account to download it!After the download is a decompression package form exists ~Files after decompression　　Here I create a new My.ini file ~ Copy the

1. Displays the names of all databases in MySQL, show databases;2. Access a database, user database_name;3. Displays the names of all the tables in the current database, show tables;4. View the current Data warehouse, select Database ();5. View all

InquireQuerying all ColumnsSELECT * from table name;Cases:SELECT * from Classes;Querying a specified columnYou can use as to specify an alias for a column or tableSelect column 1, column 2,... from table name;Cases:Select Id,name from

As business logic becomes more and more complex, the need for this query becomes more and more, and today's notes are written to keep them from forgettingORDER by admin_id　　Virtual a business, query notification table, the time is greater than today,

int: Shaping store 4 bytesDateTime: Shape store 8 bytes, you can use the MySQL time function, will not change the time zone changes, the range is largeTimestamp: Plastic Storage 4 bytes, you can use the MySQL time function, will change the time zone

sql:struct Query LanguageHost: HostsUser: UsersPassword: passwordData:Database: Databasestable: TablesColumn: Columnsfield: ColumnRow : LinePort: Portsquit: Cancel, exitExit : ExitCharSet: Character set, character encodingCOLLATE: Sorting

The MySQL default query is also not case-sensitive. But as user information, once the user name repeats, it will waste a lot of resources. Moreover, Li Kui, Li Ghost of more up, detective difficult to distinguish. To do this, either make the table

MySQL Forgot Password SolutionIf MySQL is running, first kill it: Killall-term mysqld.Start Mysql:mysql--skip-grant-tables &/etc/init.d/mysqld startYou can go to MySQL without a password.Mysql-u root-pThen there is>use MySQL>update User Set Password=

This article was also published in HTTPS://GITHUB.COM/ZHANGYACHEN/ZHANGYACHEN.GITHUB.IO/ISSUES/78 MySQL Lock Basics Referring to the structure of the Ho Dengcheng Teacher's article MySQL lock processing analysis, in the middle and

MySQL basics-triggers introduce triggers what are triggersIf you want a statement (or some statement) to be executed automatically when the event occurs. For example: Whenever a product is ordered, the quantity of the order is subtracted from the

MySQL Backup restore-incremental backup restore based on Binlog 1 IntroductionBinlog-based recovery needs to be built on a full-scale backup recovery basis. The method of using mysqldump full amount of backup is described in detail in my previous

[Master Host]Service Registration MYSQLD Install MySQL--defaults-file= "D:\IDE\mysql-5.7.20-winx64\my.ini"Modify the Registry Hkey_local_machine\system\currentcontrolset\services\mysqlInitialize Mysqld--initializeStart the net start MySQL============

MySQL source installation (mariadb 10.1.26)1. Environment deployment1 Installing CMakeSource installation Trilogy or Yum install CMake2 Installing dependent PackagesYum install-y ncurses-devel openssl-devel OpenSSL gcc gcc-c++ readline-devel

Log the issues that are encountered in MySQL.Issue One: background error: Lock wait timeout exceeded; Try restarting transactionCause: The data in the database is in read-only state and is not allowed to update.Workaround: Kill the process.Concrete

mysql-uroot-p123456-p3308mysql-uroot-p123456-p3308-h127.0.0.1Is there a difference between the 2 links?Strace mysql-uroot-p123456-p3308 get the following resultsStat ("/etc/my.cnf", 0x7fff2b1fe5a0) =-1 ENOENT (No such file or directory)Stat

A brief introduction: After a period of research, the canal has some insightTwo configuration files:1 canal.properties (System root configuration file) main parameter listCanal.properties (System root configuration file)canal.destinations= example

SELECTCount(ID) fromRd_track_infoWHEREDATE (create_time)Date_sub (Curdate (), INTERVAL7 Day);SELECTCount(ID) fromRd_track_infoWHEREDATE (create_time)=Date_sub (Curdate (), INTERVAL7 Day);SELECTCount(ID) fromRd_track_infoWHEREDATE

Statement: The material used in this column is written by the VIP students of the Kay Academy, who has the right to be anonymous and has the final right to interpret the article; The Edith Academy is designed to promote students to learn from each

Obtain the first record that meets the conditions in the second table of left join. Problem description Table 1 tableATid username title1 lily our company will conduct xx Training2 angus notifications about Autumn games3. boss will not receive any