Mysql your visual blueprint for creating open source databases- P12

Mysql your visual blueprint for creating open source databases- P12:The show tables command displays a list of tables available in the currently selected database. You can use this command when you are unsure of the exact name of a table within the database.
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Mysql your visual blueprint for creating open source databases- P12 CONFIGURE MYSQL SECURITY 11MYSQL SECURITY BASICS ySQL includes a sophisticated security system. YouM can use MySQL commands to create users and grant them privileges for a database or table. The Grant Tables The Authentication Process Internally, the MySQL server stores its usernames, When you attempt to connect to a MySQL server, the passwords, and privileges in several tables within the client encrypts your password and sends a request mysql database. This database is created when you including the username you specified to the server. The install the MySQL server. The user table within this server checks whether the username is listed in the user database stores a row for each user and a number of table and whether the password matches the encrypted fields that define the basic privileges granted to the user. password stored in that table. If they match, you are allowed to connect. The other tables in the mysql database include the host table, which stores privileges specific to particular After this initial authentication, the MySQL client hostnames, and the db table, which stores privileges authenticates each command the client sends to the granted to users for a specific database. The tables_priv server, and checks the user, db, and other tables to table stores privileges granted for specific table names, determine whether the username has the right and the columns_priv table stores privileges granted for privileges for the command being issued. only specific columns of a table. Security Commands Default Users MySQL includes three basic commands for working When you install the MySQL server, the root user is with security. The first, GRANT, grants one or more created by default. This user is granted all privileges for all privileges to a user for a database or table. If the user databases and tables, and can create additional users. The does not already exist, it is created. root user does not have a password by default, and this is a major security hole. Be sure to change the root password The REVOKE command removes one or more privileges before allowing users to access the MySQL server. from a username. It can leave a user without privileges, but does not delete users from the user table. The installation also creates an anonymous user, which allows users on the local host to connect without The SHOW GRANTS command displays the privileges specifying a username and password. This user is granted to a particular user. These are displayed as restricted to a database named test or with a name GRANT statements and can be used to recreate or beginning with test_, so this does not represent a duplicate the users privileges. serious security risk. MySQL Users and Privileges A user in MySQL is actually the combination of a You must specify a username when you use MySQL username and hostname. If a username is set up with a client programs, such as mysql or mysqladmin. If you specific host, the user can only connect from that host. are the administrator of the MySQL server, you can Users can also be configured to allow multiple hosts or create usernames and control the privileges, or all hosts. permissions, of each user. The privileges you can grant to a user include most of You use the GRANT command in MySQL to grant one or the different things that can be done with SQL queries, more privileges to a user. If the username you specify including SELECT, INSERT, and DELETE. The complete does not exist, it is created. The REVOKE command is list of privileges is included later in this chapter. the opposite. This command removes one or more privileges from a user. 207 MySQLGRANT PRIVILEGES TO USERS You can specify a database name with the * symbol, meaningM ySQL uses its own system of usernames and passwords, unrelated to the underlyin ...