General

heitml supports the MySQL database system. MySQL is very fast and free.

We very much recommend to use MYSQL tables that support transactions (as available in newer versions of MYSQL). Without transactions a page performing multiple updates can be interrupted in the middle by an error condition. Application programs must take this into account otherwise an error condition leads to an inconsistent/undesired state of the database. Note that it is not possible to avoid all possible error conditions, like network failures, users pressing the stop button of the browser, a wrong and crashing heitml application program, an unclean shut down of the Web server, or a hardware or operating system failure. As long as the database supports transatcions (as MYSQL does if you use the right table type) heitml handles these error situations correctly asking the database system to roll back all changes that were caused by the faulty request.

MySQL is also fine for applications with a read only database or that perform at most one update statement per page access. Here you can use transaction less tables and so enjoy a significant performance gain.

Installation

There are packaged versions of heitml/RADpage available for MySQL on Linux which drastically minimize installation overhead. Please refer to the heitml/RADpage Download page on which version of MySQL is supported by the latest heitml/RADpage release.

Furthermore, there are the generic versions of heitml/RADpage which come as a precompiled module, and which contain the database drivers as source code to work with any MySQL version. You need to link in the MySQL library. Follow the instructions in the README file.

Configuration

• heitmluser, heitmlpasswd are not required for MySQL, but they can be given to overwrite the MySQL defaults
• heitmldbname must give the database name
• heitmldbhost if given, the name of the host where the database server is running (if it runs on a remote machine), otherwise localhost
• heitmldbport if given, the port on the host where the database server is running