MySQL cheatsheet

Login to the database called "testdb" as "root" with "coolpass" password:
# mysql -u root -pcoolpass testdb

Let's give user "testuser" all privileges with password "coolpass"
mysql> GRANT ALL ON *.* to testuser@'localhost' IDENTIFIED BY 'coolpass';
mysql> FLUSH PRIVILEGES;

Show me all the recent users:
mysql> select * from appusers order by UserId desc limit 2;

Show me all messages that were sent today:
mysql> select * from messagecenter where DateTime like '2013-08-16%' order by DateTime desc;

My SQL logging.  Let's see what mysql database is doing.
mysql> show processlist;
The number of rows will give you an idea how busy is the db.

If you want to watch history, you can send output to a log file.
First let's find out where the log is:
mysql> SHOW VARIABLES LIKE "general_log%";
+------------------+------------------------+
| Variable_name    | Value                  |
+------------------+------------------------+
| general_log      | OFF                    |
| general_log_file | /var/lib/mysql/db2.log |
+------------------+------------------------+
2 rows in set (0.00 sec)

Let's enable logging:
mysql> SET GLOBAL general_log = 'ON';

Let's see what it's doing:
tail -f /var/lib/mysql/db2.log

Turn off loggin:
mysql> SET GLOBAL general_log = 'OFF';