Mysql > alter database;

process

1. Viewing the Version Number

show VARIABLES like '%version%'
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2. Backing up the Database

mysqldump -uroot -p --default-character-set=utf8 --databases mydatabase >d:\back.sql
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3. Import data

mysql -uroot -p mydatabase < d:\back.sql
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4. Mysql > select * from mysql;

mysql -uroot -p
show databases;
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Root forgets password

• Windows environment

  1. Close the service

  net stop mysql
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  Or turn it off in service

  2. Create password text file mysql-init. TXT

  alter user 'root'@'localhost' identified by 'newPassword';
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  3. Open the file and go to the installation directory using init-file

  mysql server\bin> mysqld.exe --init-file=c:\\mysql-init.txt
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  4. If mysql Installation Wizard is used, this parameter may be requireddefault-file

  shell> mysqld- defaults to the file = "C: \ \ ProgramData \ \ MySQL \ \ MySQL Server 8.0 \ \ my ini" - init - file = C: \ \ MySQL - init. TXTCopy the code

  5. After the service is successfully started, the created text file can be deleted

• Linux environment

  To reset your password

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• mysql

information-schema-tables

SELECT count(*) TABLES, table_schema FROM information_schema.TABLES where table_schema = 'databaseName' GROUP BY table_schema;Copy the code

reference

1. The mysql documentation