Special commands in MySQL database query: mysql DataBase Query

Special commands in MySQL database query: mysql DataBase Query

1. Install MySQL

Download the MySQL software and modify the installation path.

Install database MySQL5.7.18

Step 1: Database MySQL5.7.18 can download the corresponding version on the official website: http://www.filehorse.com/download-mysql-64,

Step 2: extract the downloaded installation package to a disk,

Step 3: configure the environment variable, create the environment variable MySQL_HOME, and enter the installation directory of MySQL,

Then insert % MYSQL_HOME % \ bin to the end of Path;

Step 4: run the command line as an administrator, press win + R and Enter cmd, right-click and run the command as an administrator.

Step 5: switch to the MySQL installation directory and use mysqld for installation:

Initialization data: mysqld -- initialize-insecure -- user = mysql,

Start the service: mysqld -- user = mysql,

Initialize mysql root password mysqladmin-u root password 'new-password ',

For more information, see https://dev.mysql.com/doc/refman/5.7/en/data-directory-initialization-mysqld.html.　

Step 6: register the service mysqld -- install MySQL

Use the net start mysql command to start the service.

Enter the mysql-u root-p command, and then enter the password entered during database initialization in step 5, as shown in:

Run the mysql Command show databases; To View tables in the database, as shown in:

This indicates that the database has been installed successfully.

Second: Special Database Query statements

In descending order, select name from data order by name desc; ---- Here, desc means sorting in descending order.

For a query of relative column positions, select name, price from data order by; ----- here, 2 and 3 indicate sorting by the second column and then by the third column.

Note: To sort multiple columns in descending order, desc must be used for each column.

Third:

What is the difference between creating a link for Navicat database software and creating a database?

Creating a link is to create a data link object that contains a database

To create a data link

Select the database link type. For MySQL, set the Link name and password port number.

Create Database in e-MySQL

In this way, the database will be created.