CodeIgniter Database Configuration

Key Architecture Takeaways

• ›
  Point 1: Full-stack architecture blueprint: CodeIgniter Database Configuration.
• ›
  Point 2: Covers MVC separation of concerns, routing pipelines, and database abstraction.
• ›
  Point 3: Modern ecosystems: Laravel 11/PHP 8.3, React 19, and Node.js LTS runtimes.

In continuation of basic configuration tutorial, now we are going to configure our database for the web application. The database is most important (Backbone) part of any application for storing and retrieve information an organised manner. In CodeIgniter database configuration comes in *database.php under /application/config*** directory. CodeIgniter currently supports following database to build any web application:

- MySQL (5.1+) via the mysql (deprecated), mysqli and pdo drivers - Oracle via the oci8 and pdo drivers - PostgreSQL via the postgre and pdo drivers - MS SQL via the mssql, sqlsrv (version 2005 and above only) and pdo drivers - SQLite via the sqlite (version 2), sqlite3 (version 3) and pdo drivers - CUBRID via the cubrid and pdo drivers - Interbase/Firebird via the ibase and pdo drivers - ODBC via the odbc and pdo drivers (you should know that ODBC is actually an abstraction layer)

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Chose any database from above for your application as per your application requirement and as familiar with you. we are using MySQL for our application.

CodeIgniter Database Configuration snippet:

$db['default'] = array(
 'dsn' => '',
 'hostname' => 'localhost',
 'username' => '',
 'password' => '',
 'database' => '',
 'dbdriver' => 'mysqli',
 'dbprefix' => '',
 'pconnect' => FALSE,
 'db_debug' => (ENVIRONMENT !== 'production'),
 'cache_on' => FALSE,
 'cachedir' => '',
 'char_set' => 'utf8',
 'dbcollat' => 'utf8_general_ci',
 'swap_pre' => '',
 'encrypt' => FALSE,
 'compress' => FALSE,
 'stricton' => FALSE,
 'failover' => array(),
 'save_queries' => TRUE
);

As we see above code snippet there are lots of parameters uses in DB config as an array(). We need not change all those parameters. You can leave those parameters its default value, except hostname, username, password, database and dbdriver.

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Hostname-- In this parameter specify the database server location. If your database locates the same server where your application runs use "localhost" for hostname parameter. If your database server runs from the different server then you have to put Domain name or IP address of database server.

Username-- In this parameter tell your database user name.

Password-- In this parameter specify your database password.

Database-- In this parameter specify your database name.

Dbdriver-- In this parameter set your database type. For example MySQL, MySQLi, Postgre SQL, ODBC, and MS SQL etc.

After Configuration snippet:

$db['default'] = array(
 'dsn' => '',
 'hostname' => 'localhost',
 'username' => 'dbuser',
 'password' => '1234',
 'database' => 'portal',
 'dbdriver' => 'mysqli',
 'dbprefix' => '',
 'pconnect' => FALSE,
 'db_debug' => FALSE,// Set FALSE if your application on production environment
 'cache_on' => FALSE,
 'cachedir' => '',
 'char_set' => 'utf8',
 'dbcollat' => 'utf8_general_ci',
 'swap_pre' => '',
 'encrypt' => FALSE,
 'compress' => FALSE,
 'stricton' => FALSE,
 'failover' => array(),
 'save_queries' => TRUE
 
);

On above snippet, you notice that *db_debug is set to FALSE. If your application is in a production environment then, it is recommended to set FALSE because of security issue. The db_debug* determines whether database errors should be displayed or not.

$active_group --

Using *$active_group* variable you can choose a connection group to make active from sets of connection group. By default, there is only one group (the 'default' group). You can simply switch to different connection by changing the value of a variable as shown below −

<?php
defined('BASEPATH') OR exit('No direct script access allowed');

//$active_group = 'default'; //comment on the defaule group

$active_group = 'conn2';   //Conn2 is active now

$query_builder = TRUE;

$db['default'] = array(
 'dsn' => '',
 'hostname' => 'localhost',
 'username' => 'dbuser',
 'password' => '1234',
 'database' => 'portal',
 'dbdriver' => 'mysqli',
 'dbprefix' => '',
 'pconnect' => FALSE,
 'db_debug' => FALSE,
 'cache_on' => FALSE,
 'cachedir' => '',
 'char_set' => 'utf8',
 'dbcollat' => 'utf8_general_ci',
 'swap_pre' => '',
 'encrypt' => FALSE,
 'compress' => FALSE,
 'stricton' => FALSE,
 'failover' => array(),
 'save_queries' => TRUE
 
);

$db['conn2'] = array(
 'dsn' => '',
 'hostname' => 'localhost',
 'username' => 'dbuser2',
 'password' => '1234',
 'database' => 'portal2',
 'dbdriver' => 'mysqli',
 'dbprefix' => '',
 'pconnect' => FALSE,
 'db_debug' => FALSE,
 'cache_on' => FALSE,
 'cachedir' => '',
 'char_set' => 'utf8',
 'dbcollat' => 'utf8_general_ci',
 'swap_pre' => '',
 'encrypt' => FALSE,
 'compress' => FALSE,
 'stricton' => FALSE,
 'failover' => array(),
 'save_queries' => TRUE
 
);

$query_builder --

The $query_builder variables determine whether or not to load the query builder class.

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