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Open Database Connectivity (ODBC) is a standard for accessing databases. ODBC is independent of programming language, database system and operating system.

 If we have it available in Ubuntu, we should install as follows: sudo apt-get install unixodbc unixodbc-dev

 The next thing we are going todo is install the driver we want to use to connect via ODBC. In this case we will install Firebird. 

The first thing you have to do is download the driver for Firebird: http://www.firebirdsql.org/en/odbc-driver/

In our case we have chosen: OdbcFb-LIB-2.0.0151.i686.gz (Linux x86)
Unpack the file " libOdbcFb.so" and copy to: /usr/lib
Then we make sure that we have installed the Firebird client library: sudo apt-get install libfbclient2
Perhaps Openoffice and other programs insist on using a driver with the name "libgds.so" to connect to the Firebird database. If this happens we will create a symbolic link as follows: ln -s /usr/lib/libfbclient.so.2 /usr/lib/libgds.so

At this point, we are ready to add some entries to the ODBC configuration file. If the files don't exist then create them.

We can create the files in:
/etc
ODBC.ini
[DBNAME] 
Description = Firebird 
Driver = Firebird 
Dbname = localhost:/var/lib/firebird/miBD.fdb 
User = SYSDBA 
Password = xxxxx 
Role = 
CharacterSet = 
ReadOnly = No 
NoWait = No

odbcinst.ini
[Firebird] 
Description = InterBase/Firebird ODBC Driver 
Driver = /usr/lib/libOdbcFb.so 
Setup = /usr/lib/libOdbcFbS.so 
Threading = 1 
FileUsage = 1 
CPTimeout = 
CPReuse = 

Now we will check that the connection actually works and can connect to the database: isql -v NombreBD +—————————————+ | Connected! | +—————————————+ 
SQL> select * from myTables; 

Attention: If you want to use ODBC from PHP, we run the following command: sudo apt-get install php5-odbc

 Finally add php.ini: [pdo] extension=pdo.so

If we want to use a database from PHP, we need to install OCI8 extension, which it will provide an API to the use of Oracle databases. Installing OCI8 on Ubuntu is not as easy as doing an apt-get, as it takes some SDK packages provided by Oracle and their distribution license prevents that can be included in Linux distributions. This means we will have to download and compile them ourselves. 

Below is the steps to follow:

 1. Install PEAR and PECL.

2. Download ''Oracle Instant Client''. We need at least the following packages 'Basic' and 'SDK'.

3. Unzip the files

The 'X' should be replaced by the appropriate version.

4. Create symbolic links.

5. Add 'instant client' to the system.

6. Compiling oci8

WARNING: If you are behind a proxy, you have to run:


7. Enter 'instantclient, / opt / oracle / instantclient' when prompted on the command line.

8.Enable the extension.

9. Restart apache2.

We should now have available OCI8 extension to use from our PHP applications.

Recently I needed to create a batch file to back up a file on a FTP from another machine. It was not as trivial as might be expected initially, but once you've found out is pretty easy, I put it here in case someone finds it useful.

You just have to create a file with execute permissions containing the following lines:


#!/bin/bash
ftp -n -v xxx.xxx.xxx.xxx << EOT
user username password
prompt
put filename
bye
EOT

I'm going to discuss a problem I've had recently and it has taken me longer than expected to know what was happening.

For a few days, randomly my server has been displaying the message:


SQLSTATE[HY000] [2002] Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock'

The Apache server was working normally, but Drupal could not access the database because the Mysql process had died.

I started looking at the trace of mysql to see may have happened. It did not show any error message.

When looking at the trace of S.O. (using dmesg) saw a memory overflow error. After doing a little research on Google, I found that Apache, when there are a greater number of connections, use all available memory on the server, causing the mysql closes before he could write anything in your log file.

The solution has been to adjust the apache settings to reduce the amount of memory consumed and leave enough room to other processes running (like MySQL).

There are many apps to learn languages ​​, but I found one that will serve us to learn to pronounce correctly: Pronunciation Dictionary.

If you are studying Spanish, for example, and don't know the difference between the pronunciation of 'vaca' and 'baca', just you open this app, search the words and hear how a native speaker pronounces them.

The good news are that we can hear the pronunciation all the time we need and if we want to hear a different person we can do it using advanced search.

I think it's a good tool to have in the mobile and can help anyone who wants to learn or improve a new language.

Amazon instances do not create a swap partition by default. If you want an easy solution to create it, we can do the following:


These instructions will create a 2Gb swap file. If you want to increase or reduce, just change the value of count=2048 in the first instruction

If we want to access external server via SSH, it is possible that if we are behind a proxy we will not have access to port 22 used by SSH. As root, edit the file sshd_config:


Edit the line which states 'Port 22' and changed it by 'Port 443'. This port is used by 'https' so it will not be closed in the proxy. Switch over to the new port by restarting SSH.