Abstract: A computer-based method of data replication of data in a programmable computer system having an ISAM database and a transaction log file, with the ISAM database having fields of tables and the transaction log file maintaining all files transactions of the ISAM database, comprising the following steps. Polling the transaction log file for file transactions of at least one selected ISAM database fields of tables by at least one data replication server. Reading the polled file transactions of the at least one selected ISAM database fields of tables by the at least one data replication server. Sending the polled file transactions of the at least one selected ISAM database fields of tables from the at least one data replication server to at least one relational database whereby the polled file transactions of the at least one selected ISAM database fields of tables sent to the at least one relational database is accessible in real time.

Abstract: A method for providing high availability in a production information system is described. The information system consists of a primary and a secondary copy running on a dual machine architecture. A backup database is added to the system which is updated daily from a transaction log. Database maintenance and archive procedures are performed on the data in the backup database relieving the primary and secondary databases of this activity. Database conversion is performed periodically, and the backup database is used to fill in for the primary and secondary databases when they are being converted.