Revoking a Zero Downtime Upgrade

A method comprising:

• initiating revocation of a zero downtime upgrade procedure upgrading a source system to a target system, the upgrade procedure preparing software for the target system in parallel to operation of the source system by selectively (i) renaming source tables of the source system, (ii) cloning the renamed source tables for the target system, (iii) equipping the cloned tables with equipped with database triggers to transfer data to target tables used by the source system according to a source database schema, (iv) generating the target tables comprising updated software content for later use by the target system while the source tables are used via a bridge database schema, and (v) sharing tables between the source database schema accessed via the bridge database schema and the target system;
• stopping upgrade activities at the target system;
• dropping the target tables and revoking any associated table structure changes;
• switching at least a portion of the target tables from use by the target system to use by the source system;
• and
• connecting the source system to the source database schema to enable use of the source system in its state prior to the initiation of the upgrade procedure.

A system comprising:

• at least one data processor;
• and
• memory storing instructions which, when executed by the at least one data processor, result in operations comprising:
• initiating revocation of a zero downtime upgrade procedure upgrading a source system to a target system, the upgrade procedure preparing software for the target system in parallel to operation of the source system by selectively (i) renaming source tables of the source system, (ii) cloning the renamed source tables for the target system, (iii) equipping the cloned tables with equipped with database triggers to transfer data to target tables used by the source system according to a source database schema, (iv) generating the target tables comprising updated software content for later use by the target system while the source tables are used via a bridge database schema, and (v) sharing tables between the source database schema accessed via the bridge database schema and the target system;
• stopping upgrade activities at the target system;
• dropping the target tables and revoking any associated table structure changes;
• switching at least a portion of the target tables from use by the target system to use by the source system;
• and
• connecting the source system to the source database schema to enable use of the source system in its state prior to the initiation of the upgrade procedure.