ChronicDB applies dynamic database upgrades with zero database downtime and zero data inconsistencies. It can relocate databases on the fly, reorganize database schemas (partition, merge, relocate, rename, and generally update fields and tables, both horizontally and vertically), reverse schema changes, and preserve execution of unmodified legacy database applications alongside their new version, all without bringing either the database or the database application down.
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ChronicDB 3.2.3