Tag Archives: Programming

Change the number of comments per page in admin interface of wordpress

Posted by on January 14, 2009 No comments | This post has 460 views.

Let’s have this situation:

You need to make a backup of your blog, you have access only in the admin interface of wordpress and you have 3000+ comments containing spam in the ‘awaiting moderation’ state. Do you spend your day selecting 20 comments at a time and hittind the delete button? Hell, NO!

You hack the edit-comments.php file located in the wp-admin folder.
Locate the following line:

$comments_per_page = apply_filters('comments_per_page', 20, $comment_status);

Now you need to change the figure 20 to another figure, e.g. 100 so that it looks like this:

$comments_per_page = apply_filters('comments_per_page', 100, $comment_status);

Save the file and check the display of the comments in the admin interface.

Reset the root password on MySQL

Posted by on May 7, 2008 No comments | This post has 796 views.

Have you ever forgotten the root password on one of your MySQL servers?
This is a quick h00tow (how to) reset your MySQL root password. It does require root access on your server.

First things first. Log in as root and stop the mysql daemon. Now lets start up the mysql daemon and skip the grant tables which store the passwords.
mysqld_safe --skip-grant-tables
You should see mysqld start up successfully. If not, well you have bigger issues. Now you should be able to connect to mysql without a password.
mysql --user=root mysql

update user set Password=PASSWORD('YourNewRootPassword');
flush privileges;
exit;

If you are using Ubuntu 8.04 Hardy Heron, when you try to restart the mysql service using
sudo /etc/init.d/mysql restart
you’ll get an error like

error: 'Access denied for user 'debian-sys-maint'@'localhost' (using password: YES)'

The debian_sys_maint user is the one used by mysql user system under debian sytems.In order to fix this (seeming to be a grant error) do like this:

Save the password of debian-sys-maint user which is localized in /etc/mysql/debian.cnf file (readable only by root):


sudo more /etc/mysql/debian.cnf
# Automatically generated for Debian scripts. DO NOT TOUCH!
[client]
host = localhost
user = debian-sys-maint
password = lP3Ufasdas3AVm7EdC
socket = /var/run/mysqld/mysqld.sock
[mysql_upgrade]
user = debian-sys-maint
password = lP3Ufasdas3AVm7EdC
socket = /var/run/mysqld/mysqld.sock
basedir = /usr
root@scrat:/etc/mysql#

Save somewhere this password, then connect on mysql under root:
mysql -u root -p

and execute following command:

GRANT ALL PRIVILEGES ON *.* TO ‘debian-sys-maint’@'localhost’
IDENTIFIED BY ‘your_password’ WITH GRANT OPTION;

Everything should be OK now.

There is another method to reset the root password on MySQL in Ubuntu:
sudo /etc/init.d/mysql reset-password

Unp

Posted by on February 20, 2008 No comments | This post has 597 views.

Unp is a small perl script which makes extraction of any archive files a bit easier. It support several compressors and archiver programs, chooses the right one(s) automatically and extracts one or more files in one go.

Instalation:
sudo apt-get install unp

Usage:
usage: unp file [file]...
file: compressed file(s) to expand

Use -- to pass arguments to external programs, eg. some tar options:
unp fastgl.tgz xmnt.tgz -- -C /tmp

Special option:
-f Continue even if program availability checks fail
-u For Debian packages:
- extract data.tar.gz after each operation
- extract control.tar.gz in control//
For other archives:
- create directory /
- extract contents there

currently supported extensions and formats are
tar[.gz,.bz2], gz, bz2, Z, ar/deb, rpm, shar, rar, arj, zip, LHa, cab, ace,
tnef, uu (mail, news), mime, hqx, sea, zoo, pmd, cpio, afio, lzop

Problem:
It doesn’t extract files from RAR archives with full path!

How-To create a MySQL database and set privileges to a user

Posted by on September 19, 2007 No comments | This post has 534 views.

MySQL is a widely spread SQL database management system mainly used on LAMP (Linux/Apache/MySQL/PHP) projects.
In order to be able to use a database, one needs to create: a new database, give access permission to the database server to a database user and finally grant all right to that specific database to this user.

This tutorial will explain how to create a new database and give a user the appropriate grant permissions.

For the purpose of this tutorial, I will explain how to create a database and user for the music player Amarok. In order to index its music collection, Amarok quand use a mysql backend.

The requirement for this set up is to have access to a database. We are going to create a database called amarok which will be accessible from localhost to user amarok idetified by the password amarok….
Obviously, we need to to have a mysql server installed as well as amarok:
sudo apt-get install mysql-server amarok

On a default settings, mysql root user do not need a password to authenticate from localhost. In this case, ou can login as root on your mysql server using:
mysql -u root
If a password is required, use the extra switch -p:
mysql -u root -p
Enter password.
Now that you are logged in, we create a database:


mysql> create database amarokdb;
Query OK, 1 row affected (0.00 sec)

We allow user amarokuser to connect to the server from localhost using the password amarokpasswd:

mysql> grant usage on *.* to amarokuser@localhost identified by 'amarokpasswd';
Query OK, 0 rows affected (0.00 sec)

And finally we grant all privileges on the amarok database to this user:

mysql> grant all privileges on amarokdb.* to amarokuser@localhost ;
Query OK, 0 rows affected (0.00 sec)

And that’s it. You can now check that you can connect to the MySQL server using this command:
mysql -u amarokuser -p'amarokpasswd' amarokdb