Install Photoscape on Ubuntu 13.10

Firstly, we have to install the latest wine.
Run this command in terminal

sudo add-apt-repository ppa:ubuntu-wine/ppa
sudo apt-get update
sudo apt-get install wine1.7

Download the Photoscape. Open the download folder and right click on the Photoscape file, choose 'Open With Wine Windows Program Loader'.

Once we've finished the installation, we can open Photoscape from Unity Dash.

That's all.

Reference:
http://www.winehq.org/download/ubuntu

Yii migration safeUp() is not working

I tried to create a table using the safeUp() function. Here's the content of the migration file

class m140113_223038_create_test_tables extends CDbMigration
{
 public function up()
 {
 }

 public function down()
 {
 }

 public function safeUp()
 {
  $this->createTable('tbl_test',array(
   'id'=>'pk',
   'name'=>'string NOT NULL',
   ),'ENGINE=InnoDB');
 }

 public function safeDown()
 {
  $this->dropTable('tbl_test');
 }
}

However, it won't create a new table. The solution is actually very simple. If we want to use safeUp() function, we have to make sure that there's no up() function in the code. So, we have to remove both up() and down() function.

class m140113_223038_create_test_tables extends CDbMigration
{
 public function safeUp()
 {
  $this->createTable('tbl_test',array(
   'id'=>'pk',
   'name'=>'string NOT NULL',
   ),'ENGINE=InnoDB');
 }

 public function safeDown()
 {
  $this->dropTable('tbl_test');
 }
}

Reference:
http://stackoverflow.com/questions/18126773/yii-framework-yic-migrate-command-doesnt-work

Yii shell is not working

I tried to run yii shell on Ubuntu 13.10 using this command:

protected/yiic shell

But it's not working. A long lines of HTML output was displayed on screen.

I found 2 solutions on the web:
1st: use this command instead:

protected/yiic shell protected/config/main.php

2nd: modify protected/config/main.php, and add this line at the top:

date_default_timezone_set('UTC')

References:
http://stackoverflow.com/questions/11792981/yii-command-tool-not-work
http://stackoverflow.com/questions/7841523/yiic-command-line-tool-outputting-code-instead-of-opening-shell

Install phpmyadmin on Ubuntu 13.10

To install phpmyadmin, run

sudo apt-get install phpmyadmin

When I open http://localhost/phpmyadmin, it says ".../phpmyadmin/ was not found on this server".

How to fix it?
Firstly, open /etc/apache2/apache2.conf
You can open it by pressing Alt+F2, then type

gksudo gedit /etc/apache2/apache2.conf

Note: if gksudo is not installed, you can install it using "sudo apt-get install gksu".

Then go to the end of the file and type

Include /etc/phpmyadmin/apache.conf

Save the file, then restart the apache using this command

sudo /etc/init.d/apache2 restart

Done.

Install LAMP on Ubuntu 13.10

Open the terminal, then run

sudo apt-get install lamp-server^

^ sign is a Tasksel command (https://help.ubuntu.com/community/Tasksel)

Now, let's make a new php file to test.
Firstly, I'm going to open a text editor called gedit as a root user.

Press Alt + F2, then run

gksudo gedit

Note: if gksudo is not installed, you can install it using

sudo apt-get install gksu

Then type this php code

<?php
phpinfo();
?>

And save it in /var/www/ folder. I use "phpinfo.php" as the file name.
Now, open it in web browser: http:/localhost/phpinfo.php
You should be able to see the output of phpinfo().
LAMP server installation is done.
References:
Source: http://gregrickaby.com/how-to-install-lamp-on-ubuntu/

Installing Ubuntu 13.10 alongside Windows 7 on Samsung Netbook N150

I want to install Ubuntu 13.10 alongside Windows 7.

Firstly, download the Ubuntu 13.10 ISO (I chose the 32 bit version because my netbook has 1GB memory). Then, create a bootable USB stick using Pen Drive Linux (http://www.ubuntu.com/download/desktop/create-a-usb-stick-on-windows).

Insert the USB to the netbook, then turn the netbook on. It will automatically load the Ubuntu. I chose the install ubuntu alongside windows option. Then I had to setup the wireless network. However, the installation suddenly quit and it restart the netbook.

The cause of the problem was the primary partition in the netbook harddisk. The harddisk already had 4 primary partition. I tried to delete one of the partition which I didn't need anymore.

Then I tried the installation process again, and this time it was successful.

Improve MySQL performance

I've got a problem with with my MySQL database (running on Ubuntu). I tried to run a query on a table (InnoDB) containing 250 thousand rows. The result of the query is only 3 rows. However, it took 4 minutes to get the result.

How to improve the performance?
Open the /etc/my.cnf in the text editor
sudo gedit /etc/my.cnf

Then go to [myslqd] section and add the buffer size.
The default size is 8M. In my case, I increased it to 256M
innodb_buffer_pool_size = 256M

Then restart mysql
sudo /etc/init.d/mysqld restart

To check the change, go to mysql command line and run SHOW VARIABLES.

DONE.

Source:
http://www.cowboycoded.com/2009/08/26/a-quick-performance-tune-for-mysql-innodb_buffer_pool_size/