The XAMPP from Apache Friends is a collection of free open source apps that make it easy to install Apache distribution containing MySQL, PHP and Perl. There are four XAMPP distributions for Windows, Linux, Mac OS X and Solaris. To set up an Apache web server with XAMPP, simply download and extract XAMPP, and the Apache HTTPD web server is ready after one or two more auto-execute scripts. There are no changes to the Windows registry (unless you’re using Widows installer version of XAMPP) and it’s not necessary to edit any configuration files.

However, by default, InnoDB MySQL database storage engine is not enabled in the my.cnf configuration file. If a webmaster plans to use InnoDB features, such as one to many or many to many table relationships on foreign key constraints, or transaction-safe commands such as commit, rollback and crash recovery capabilities.

To enable the support of MySQL server on InnoDB storage engine, locate the “my.cnf” config file (normally in /installation_path/xampp/mysql/bin/ directory), and edit the my.cnf with any text editor such as vi.

Search and locate each of the following lines (except the lines in italic where they’re comments):

- Comment the following line to unskip and use InnoDB
skip-innodb 

- Uncomment the following options for InnoDB database if you are using InnoDB tables.
#innodb_data_home_dir = C:/xampp/xampp/mysql/data/ 
#innodb_data_file_path = ibdata1:10M:autoextend 
#innodb_log_group_home_dir = C:/xampp/xampp/mysql/data/ 
#innodb_log_arch_dir = C:/xampp/xampp/mysql/data/ 

- Uncomment the lines and set innodb_buffer_pool_size up to 50% - 80% of RAM for optimization of InnoDB databases, try not to memory usage too high.
#set-variable = innodb_buffer_pool_size=16M 
#set-variable = innodb_additional_mem_pool_size=2M 

- Uncomment the lines and set innodb_log_file_size to 25% of InnoDB buffer pool size for optimisation.
#set-variable = innodb_log_file_size=5M 
#set-variable = innodb_log_buffer_size=8M 
#innodb_flush_log_at_trx_commit=1 
#set-variable = innodb_lock_wait_timeout=50 

After modification, the code for each lines should look like this:

# skip-innodb 

innodb_data_home_dir = C:/xampp/xampp/mysql/data/ 
innodb_data_file_path = ibdata1:10M:autoextend 
innodb_log_group_home_dir = C:/xampp/xampp/mysql/data/ 
innodb_log_arch_dir = C:/xampp/xampp/mysql/data/ 

set-variable = innodb_buffer_pool_size=16M 
set-variable = innodb_additional_mem_pool_size=2M 

set-variable = innodb_log_file_size=5M 
set-variable = innodb_log_buffer_size=8M 
innodb_flush_log_at_trx_commit=1 
set-variable = innodb_lock_wait_timeout=50 

When InnoDB is not enable and MySQL uses MyISAM database storage engine instead, some errors that may be returned include:

Undefined GET property or variable in ‘A_Class’ class: A_Class_Object

Fatal error: Call to undefined method Object::Function() in /xampp/htdocs/wwwroot/a_page.php on line 87