Revoking MySQL Permissions

Usage:

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mysql> revoke PRIVILEGES [, GRANT OPTION] from 'USERNAME'@'SERVER';
mysql> flush privileges;

Example:

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mysql> revoke all privileges, grant option from 'comsiteuatusr'@'10.135.7.114';
Query OK, 0 rows affected (0.00 sec)
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mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)

See Also

How to install MySQL Server on Debian Linux

While installing MySQL Server it is always good to keep in mind that the logs and data folders will potentially have a big size. By default MySQL keeps them in the root mount point (i.e. ‘/’). That may cause your database server system disk to get full, which is never a good idea.

This article describes how to move these two folders to ‘/home’ which is ideally mounted into another disk and has enough space to keep your database data and logs.

First, I install the required apt-get packages as follows:

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apt-get update
apt-get install mysql-server

To check the status:

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/etc/init.d/mysql status
/usr/bin/mysqladmin Ver 8.41 Distrib 5.0.51a, for debian-linux-gnu on i486
Copyright (C) 2000-2006 MySQL AB
This software comes with ABSOLUTELY NO WARRANTY. This is free software,
and you are welcome to modify and redistribute it under the GPL license
Server version 5.0.51a-24
Protocol version 10
Connection Localhost via UNIX socket
UNIX socket /var/run/mysqld/mysqld.sock
Uptime: 3 sec
Threads: 1 Questions: 78 Slow queries: 0 Opens: 23 Flush tables: 1
Open tables: 17 Queries per second avg: 26.000.

Now, stop MySQL, move the folders to the right location, reconfigure MySQL and start again:

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# Stop MySQL
/etc/init.d/mysql stop
# Move and reconfigure data
mkdir /home/mysql
mv /var/lib/mysql /home/mysql/mysql-data
ln -s /home/mysql/mysql-data/ /var/lib/mysql
# Move and reconfigure logs
mv /var/log/mysql/ /home/mysql/mysql-logs
ln -s /home/mysql/mysql-logs/ /var/log/mysql
# Start MySQL and check that everything is OK
/etc/init.d/mysql start
/etc/init.d/mysql status
/usr/bin/mysqladmin Ver 8.41 Distrib 5.0.51a, for debian-linux-gnu on i486
Copyright (C) 2000-2006 MySQL AB
This software comes with ABSOLUTELY NO WARRANTY. This is free software,
and you are welcome to modify and redistribute it under the GPL license
Server version 5.0.51a-24
Protocol version 10
Connection Localhost via UNIX socket
UNIX socket /var/run/mysqld/mysqld.sock
Uptime: 14 sec
Threads: 1 Questions: 78 Slow queries: 0 Opens: 23 Flush tables: 1
Open tables: 17 Queries per second avg: 5.571.

These are some settings that I usually put on the /etc/mysql/my.cnf configuration file:

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# Here you can see queries with especially long duration
log_slow_queries = /var/log/mysql/mysql-slow.log
long_query_time = 1
log-queries-not-using-indexes
# A server-id unique
server-id = 177
log-bin = /var/log/mysql/mysql-bin.log
log-bin-index = /var/log/mysql/mysql-bin.log
innodb_file_per_table
# Unique log names (this prevents replication breaking upon hostname change :-)
relay-log = iamalsounique98127-relay-bin
relay-log-index = iamalsounique98127-relay-bin
# Taking care of the auto-increment values (for multi-master replication)
auto_increment_increment = 10
auto_increment_offset = 1

For these changes to take effect, you would need to restart MySQL:

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/etc/init.d/mysql restart

If you want to ignore databases or tables you may use the following options:

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binlog_ignore_db = information_schema
replicate_ignore_db = information_schema
binlog_ignore_db = mysql
replicate_ignore_db = mysql
# Ignore all the cache* tables which have caused DUPLICATE
# ENTRY issues. Unai.
replicate_wild_ignore_table = exampledb.cache%

Having ‘binlog_ignore_db’ is enough to exclude databases from replication BUT having ‘replicate_ignore_db’ as well will make things clearer since the databases that are being ignored will appear in both the ‘SHOW SLAVE STATUS\G’ and ‘SHOW MASTER STATUS\G’.