The use of MySQL under Linux

The use of MySQL under Linux

1. Install the mysql command: sudo apt-get install-y mysql-server

2. Start the mysql command: sudo service mysql start (root permission is required to use it, without any prompt after startup)

3. Enter the mysql command after startup: mysql-u username-p password

4. Create a library: create database database_name

5. Display the list of libraries: *. Show databases

6. Select a library for operation: use database_name

7. Create a table: create table table name (column name 1 data type, column name 2 data type, …... )

Create table teacher (id int auto_increment not null primary key

Name char

Address varchar (50) default "Shenzhen"

Year date

);

Id is set as the primary key and automatically set, that is, you don't have to write to the id field when you add it.

8. Insert by row: insert into table name values (value 1, value 2,... )

Insert by column: insert into table name (column 1, column 2,... ) values (value 1, value 2,... )

9. Display the information in the table: select * from table name

10. Display the table in the library: use mysql; (open the library you want to operate)

Show tables; (display the tables in the library)

Constraint: not null (the data type is followed by not null to force the column not to accept null values).

12. Modify the data in the table: update table name set column name = new value where column name = a value

13. Delete:

① deletes rows from the table: delete

② deletes the row where the A value is located: delete from table name where column name = A value

③ deletes all lines: delete from table_name; or (delete * from table_name)

Note: open the library (use mysql;) when manipulating the library and the tables in the library.