Difference between revisions of "MySQL"

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m (Fixed spacing (botched by section-specific edit) and added reminder for importing SQL statements.)
m (Added tips for showing the database character set and engine type.)
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* <syntaxhighlight lang="mysql">SHOW GRANTS;</syntaxhighlight>
 
* <syntaxhighlight lang="mysql">SHOW GRANTS;</syntaxhighlight>
 
** For current user
 
** For current user
 +
 +
 +
== Show the character set for a database ==
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<syntaxhighlight lang="mysql">
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SHOW CREATE DATABASE database_name;
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</syntaxhighlight>
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== Show the database engine type ==
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<syntaxhighlight lang="mysql">
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USE DATABASE database_name;
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SHOW CREATE TABLE table_name;
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</syntaxhighlight>
  
  

Revision as of 23:33, 5 March 2014


Character length restrictions

[1] [2]

  • 64 characters for database name
  • 16 characters for user name
  •  ? characters for password length
    • Seems to be dependent on the version


Create a database

CREATE DATABASE my_test_db CHARACTER SET utf8;


Create a user for that database with full privileges to it

CREATE USER 'my_test_db_usr'@'localhost' IDENTIFIED BY 'INITIAL_PASSWORD';
GRANT ALL PRIVILEGES ON my_test_db.* TO 'my_test_db_usr'@'localhost';


Reset password for user account

SET PASSWORD for 'my_test_db_usr'@'localhost' = PASSWORD('REAL_PASSWORD_HERE');


Import or run SQL statements from file

source my-sql-file.sql;


Delete user account

DROP USER 'my_test_db_usr'@'localhost';


Delete database

DROP DATABASE 'my_test_db';


Resetting the root user account

[3] [4] The safest approach is to add the statement containing the password to a file and run

mysqld_safe --init-file=/home/me/FILE &

followed by:

sudo /etc/init.d/mysql stop
sudo mysqld --skip-grant-tables &
mysql -u root mysql
UPDATE user SET Password=PASSWORD('YOURNEWPASSWORD') WHERE User='root'; FLUSH PRIVILEGES; exit;


Viewing privileges granted to a user

[5] [6]

  • select * from mysql.user;
    
    • Parse results by eye (not pretty)
  • SHOW GRANTS FOR username@ipaddress;
    
  • SHOW GRANTS;
    
    • For current user


Show the character set for a database

SHOW CREATE DATABASE database_name;


Show the database engine type

USE DATABASE database_name;
SHOW CREATE TABLE table_name;


References