Mysqldump data backup

In our last blog, we talked about using mysqlbinlog Tools (mysql Native tools ) Mind parsing a large number of binlog Log files , And use binary logs Data recovery Application practice of , In this blog, let's talk about the command of turning off data backup first , Because we usually work in shell Next , And deployed in the background server or cloud mysql, Most have made some restrictions , We may not be able to connect directly to the database of the background service locally 3306 On port , Generally, there will be intermediate keys of networks such as firewalls , No conditions GUI（ GUI tools ） Mouse operation for data backup and so on , Only by command , And the command is also the fastest , So this blog talks about commonly used The data backup , We usually pass mysqldump Conduct .

stay linux shell Execute the following command , You can mytest Library user The data of the table is exported to .sql In file （ Exporting is not just data ,SQL Statements are also exported ）

vim user.sql see user.sql The contents of the document are as follows ：


Now? mytest Inside the library , We deleted the table , Or we are moving towards data migration , Rebuild this table on another library . We have this sql Script in root Under the root directory , Not enough permissions , It should be executed under ordinary users , So the user.sql Move to ordinary users （ Or we can start with ordinary users mysqldump -u root -p mytest user > ~/user.sql hold mytest Library user The data of the table is exported to .sql In file , There is no need to perform the next steps , Direct execution source /home/admin/user.sql, You can recover user Tables and data ）



Now? user.sql yes root The file of , We change a subordinate , So that ordinary users can also operate

And then we source, Is equivalent to .sql Execute the script again


user The table and data are all recovered , With .sql Script for , Can be in any mysql Rebuild the database table and data on the database

We can also export pure table data directly

user.txt The contents are as follows ：

This way user All the data in the table are exported , We'll use it again python perhaps go When writing some scripts for data analysis , Can pass -t As a separator, get the data of each field for additional data analysis , For example, analyze user behavior , Create user portraits, etc .

mysqldump Data backup command summary

• Export database and table creation SQL

// Export all libraries 
mysqldump -u  user name  -p --all-databases > ~/xxx.sql
// You can export multiple libraries at a time 
mysqldump -u  user name  -p --databases db1[db2] > ~/xxx.sql
// Export the library or a table in the Library 
mysqldump -u  user name  -p dbname [tablename]> ~/xxx.sql

• Export pure data

mysql -u  user name  -p -D school -e 'select * from user where age>10' > ~/user.txt

• Via backup .sql, Import data , Building database and building tables

Sign in mysql, stay mysql Of shell Execute the following statement on

source ~/school.sql

Or directly at linux Of shell perform

cat ~/data.sql|mysql -u root -p

In this way, the data we backed up before can be sent to mysql In the library table of