Add, delete, modify, and query MySQL

MySQL does not take a long time to learn. database operations simply add records, search records, delete records, and modify records.
Summarize the following commands to share with you:
Connection command: mysql-H [host address]-U [user name]-P [User Password]
Create Database: Create Database [database name]
Show all databases: Show databases;
Open Database: use [database name]
Status of the currently selected Database: select database ();
Create a data table: Create Table [Table name] ([field name] [field type] ([field requirements]) [field parameters], ......);
Display the data table field: Describe table name;
Current Database Data Table Structure: show tables;
Change table
Alter table [Table name] add column [field name] datatype
Note: Add a column (the syntax of a column is not deleted.
Alter table [Table name] add primary key ([field name])
Note: You can change the table definition to set a column as a primary key.
Alter table [Table name] Drop primary key ([field name])
Delete the definition of the primary key.
Show columns from tablename;
Delete Database: drop database [database name];
Delete table: Drop table [Table name];
Data Operations
Add: insert into [Table name] values ('','',... ordered data );
Query: Select * from [Table name] Where ([condition]);
Create index [index file name] on [Table name] ([field name]);
Delete: delete from [Table name] Where ([condition]);
Modify: update [Table name] Set [Modification content such as name = 'Mary '] Where [condition];

Import external data text:
1. Execute External SQL scripts
Run mysql <input. SQL on the current database.
Run the following command on the specified database: MySQL [Table name] <input. SQL
2. Data Import command load data local infile "[file name]" into table [Table name];
Back up the database: (under DOS)
Mysqldump -- opt school> school. bbb