Zero downtime upgrade of systems with database-side replication

A non-transitory computer-readable storage medium coupled to one or more processors and having instructions stored thereon which, when executed by the one or more processors, cause the one or more processors to perform operations for replication of data from a first database system to a second database system during upgrade of an application from a first version to a second version, the application interacting with the data in the first database system and a consumer consuming data from the second database system, the operations comprising:

• providing, by a deploy tool, one or more source-side clone data components in the first database system, each source-side clone data component being a copy of a respective data component;
• defining, by the deploy tool, a source-side green access schema in the first database system, the source-side green access schema providing one or more views to the one or more source-side clone data components based on the second version of the application;
• providing, by a replication system and based on one or more statements received from the deploy tool, one or more consumer-side clone data components in the second database system, each consumer-side clone data component being a copy of a respective data component;
• defining, by a replication system and based on one or more statements received from the deploy tool, a consumer-side green access schema in the second database system, the consumer-side green access schema providing one or more views to the one or more consumer-side clone data components based on the second version of the application;
• during execution of the upgrade:
• replicating, by a first handler of the replication system, data from at least one source-side data component to a respective consumer-side component, the first handler corresponding to the first version of the application;
• and
• after completion of the upgrade:
• replicating, by a second handler of the replication system, data from at least one source-side data component to a respective consumer-side component, the second handler corresponding to the second version of the application.

A system, comprising:

• a computing device;
• and
• a computer-readable storage device coupled to the computing device and having instructions stored thereon which, when executed by the computing device, cause the computing device to perform operations for replication of data from a first database system to a second database system during upgrade of an application from a first version to a second version, the application interacting with the data in the first database system and a consumer consuming data from the second database system, the operations comprising:
• providing, by a deploy tool, one or more source-side clone data components in the first database system, each source-side clone data component being a copy of a respective data component;
• defining, by the deploy tool, a source-side green access schema in the first database system, the source-side green access schema providing one or more views to the one or more source-side clone data components based on the second version of the application;
• providing, by a replication system and based on one or more statements received from the deploy tool, one or more consumer-side clone data components in the second database system, each consumer-side clone data component being a copy of a respective data component;
• defining, by a replication system and based on one or more statements received from the deploy tool, a consumer-side green access schema in the second database system, the consumer-side green access schema providing one or more views to the one or more consumer-side clone data components based on the second version of the application;
• during execution of the upgrade:
• replicating, by a first handler of the replication system, data from at least one source-side data component to a respective consumer-side component, the first handler corresponding to the first version of the application;
• and
• after completion of the upgrade:
• replicating, by a second handler of the replication system, data from at least one source-side data component to a respective consumer-side component, the second handler corresponding to the second version of the application.