Patent ID: 7831636

Claim:
A method for configuring a transaction-based host environment for the migration from a first system platform to a second system platform, wherein access to the host environment from a decentralised environment is maintained during the migration, comprising the steps: providing at least one database of a first type on the first system platform, wherein the first type of database is not migrated to the second system platform or is migrated at least one of unchanged in content and with an unchanged logical data model; providing at least one database of a second type on the first system platform, wherein on migration to the second system platform the second type of database is transformed into a third type of database that is at least one of changed in content and changed in relation to a logical data model; replacing, during the migration a first type of transaction, which on the first system platform accessed both the first type of database and the second type of database, by a second type of transaction and a third type of transaction in the host environment, wherein the second type of transaction accesses the first type of database and not the second type of database, and the third type of transaction accesses the second type of database and not the first type of database; receiving a request for a transaction of the first type from the decentralized environment; in response to receipt of the request during the migration, initiating transactions of the second and third type in the host environment; and upon completion of the migration of the second type of database to the third type of database the method further comprising the steps of: replacing the first type of transaction with a first post migration type of transaction and a second post migration type of transaction, wherein the first post migration type of transaction accesses the first type of database and not the second or third types of databases, and the second post migration type of transaction accesses the third type of database and not the first or second types of databases; in response to receipt of the request after the migration, initiating transactions of the first and second post migrations types in the host environment; and disabling the second type of database from the host environment.