MySQL basic command----view, create, delete libraries and tables in a Linux environment

Case two, viewing the database

MySQL is a database management system that supports running multiple libraries, each of which is the equivalent of a container that holds many tables. Data exists in these tables, so viewing, creating, deleting libraries and tables is essential in your work.

One, view

1. See which libraries are in the current server

Use command: SHOW DATABASES; View library Information

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2. See which tables are currently in use in the library

Using the command: use MySQL; Switch to a table named MySQL using the use command

Use command: SHOW TABLES; View table Information

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3. View the structure of the table

Use command: DESCRIBE mysql.user; MySQL is the library name and user is the table name.

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Second, create and delete libraries and tables

1, create a new library

Using the command: Create database name;//creating a library named name

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2, create a new table

Command syntax: CREATE table table name (field 1 name type, field 2 name Type, ..., PRIMARY key (primary key name))

Using the command: use name;

CREATE TABLE Users (user_name char (+) not NULL, user_passwd char ("DEFAULT", PRIMARY KEY (user_name));

Create a table named users with field name 1 of user_name 16 bytes and cannot be empty. The field Name 2 is user_passwd 48 bytes, the default null type is used, and the primary key name is user_name.

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3, delete a table

Use the command: Drop table name.users;//delete the Users table in the name library

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4, delete a library

Use command: Drop database name;//delete name Library

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This article is from the "New Start" blog, so be sure to keep this source http://yuanshuai.blog.51cto.com/10539781/1729801

MySQL basic command----view, create, delete libraries and tables in a Linux environment