This tutorial explains how to install MySQL and how to create and query a database. It includes important SQL statements which you need to use to create, update and read from database tables.
MySQL is a open source relational database. Applications can use this database to persist data.
This tutorial covers the installation of MySQL and the usage of the database.
To work in
MySQL databases you use
SQL is a query language for relational databases.
Under Ubuntu you can install MySQL with the following command:
sudo apt-get install mysql-server
The installation procedure allow you to set the root password.
Under Windows download the community edition from http://dev.mysql.com/downloads/. For windows you have installer program available which guides you through the installation process.
MySQL provides the
mysql command line interface for administrative work.
To connect to the MySQL database server use the following command:
# connect as root to MySQL server mysql -u root -p
To create a database and a user with access rights, use the following commands.
CREATE DATABASE vogella_blog; CREATE USER 'myblog'@'localhost' IDENTIFIED BY 'my_password'; GRANT ALL PRIVILEGES ON * . * TO 'myblog'@'localhost'; GRANT ALL ON vogella_blog.* TO 'myblog'@'localhost' IDENTIFIED BY 'my_password' WITH GRANT OPTION; FLUSH PRIVILEGES;
Once you have created a database on this server you can also connect directory to the database with the following command.
mysql db_name -u user -pmypassword
The default port of the database server is 3306. For example, the Java JDBC connection string to connect to the iotcloud database would be jdbc:mysql://localhost:3306/iotcloud.
To see all databases and to connect to the
show databases; connect vogella_blog;
List all tables in the currently used database;
For example, to show the content of a
wp_users of table use the following command.
SELECT wp_users.* FROM wp_users ;
mysql command line interface allows you to export your database and import existing backups.
mysqldump command provides the option to create backup of your database, e.g. export your database.
To export the database use the following command.
# creates a dump of the database vogella_blog mysqldump vogella_blog > vogella_blog.sql -p
To import an existing SQL dump file use the following command.
# vogella_blog.sql is your exported SQL file # use option -p to enter your password mysql vogella_blog < /var/www/vhosts/vogella.com/vogella_blog.sql -p