![]() Making matters even more confusing, each row in the user table has its own password field-meaning that the same user name can have wildly different passwords and privileges depending on what IP address they access the MySQL server from.īy default, MySQL only exposes itself to the localhost interface-meaning there's only one possible host to access it from-so this is a moot point on a default-configured MySQL instance. meaning you can have multiple "users" with the same username! The answer is a bit frustrating-MySQL's user accounts are individual to each host that a user might log in from. If you're really a MySQL newbie, you might be wondering what the host column is really about. You can turn off this feature to get a quicker startup with -A Reading table information for completion of table and column names Now your command is SELECT host,user FROM user and your results are much nicer to read: Unfortunately, there are a lot of columns in the er table-too many to fit on the screen without horizontal text wrapping, resulting in an unreadable mess.įor more useful, less mangled results, try SELECTing just the columns you're actually interested in-in this case, host and user. The users who can log in to your MySQL databases can be found in the er table, which can be queried with SELECT * from er (or USE mysql SELECT * from user if you prefer). These databases are the "guts" of your MySQL server itself and for the most part shouldn't be mucked around with directly as though they were normal data. This is pretty straightforward and does just what you'd think-on a new system, you'll see information_schema, performance_schema, sys, and mysql. To see a list of databases running in your MySQL instance, use the statement show databases. (Note: commands entered into the console must end with a semicolon.) Creating databases and users To get out of the MySQL console, you can just exit at any time. Once you know the password for debian-sys-maint on your local system, you can log in to your new MySQL server with mysql -u debian-sys-maint -p-the system will ask you for the password thanks to the -p flag you specified, and then you're in! This file notes the automatically created mysql superadmin account name and password the name is debian-sys-maint, and the password is randomly generated at installation time (and, therefore, different on each system). The answer here-on Ubuntu or Debian-derived distributions, at least-lies in the file /etc/mysql/debian.cnf. What's less obvious is how you get into the little bugger once it's running. Once the package is downloaded and installed, mysql is fired up automatically (and will be after each system reboot). If the CREATE DATABASE statement has an IF NOT EXISTS clause in it, then the result of the SHOW CREATE DATABASE Statement of the respective database also contains the IF NOT EXISTS clause.Installing MySQL on a fresh Ubuntu instance is quite simple: sudo apt update if necessary, then sudo apt install mysql-server and you're off to the races. If you use the IF NOT EXISTS clause along with the CREATE statement as shown below a new database will be created and if a database with the given name, already exists the query will be ignored. If you try to create a database with an existing name an error will be generated −ĮRROR 2006 (HY000): MySQL server has gone awayĮRROR 1007 (HY000): Can't create database 'mydatabase' database exists | mydatabase | CREATE DATABASE `mydatabase` /*!40100 DEFAULT CHARACTER SET utf8 */ /*!80016 DEFAULT ENCRYPTION='Y' */ /* READ ONLY = 1 */ | ![]() You can verify the characteristics of the created database as shown below − Mysql> ALTER DATABASE mydatabase CHARACTER SET utf8 COLLATE utf8_general_ci ENCRYPTION = 'Y' READ ONLY = 1 Suppose we have altered the above created database as shown below − ![]() Once you alter the characteristics of a database using the ALTER statement the SHOW CREATE DATABASE Statement displays the query along with the characteristics. | sampleDatabase | CREATE DATABASE `sampleDatabase` /*!40100 DEFAULT CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci */ /*!80016 DEFAULT ENCRYPTION='N' */ | The following query displays the query used to create the database − Suppose we have created a database as shown below − Where, database_name is the name of the database. Syntaxįollowing is the syntax of the SHOW CREATE DATABASE statement − This displays the create statements along with the clauses. This query shows/displays the statement used to create the specified database. ![]()
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