DATA MIGRATION SYSTEM

Described are techniques and systems to migrate data from a first data structure to a second data structure stored in datastores which are replicated with one another. A “hot” datastore is replicated with one or more “warm” datastores. Triggers maintain consistency between the first data structure and the second data structure. Migration may involve testing using the second data structure of the “warm” datastore. Data processed by the first data structure on the “hot” datastore is distributed via replication to the “warm” datastore, and then by a trigger to the second data structure. Data processed by the second data structure on the “warm” datastore is distributed via trigger to the first data structure, and then by replication to the “hot” datastore. Once performance of the second data structure is deemed acceptable, the “warm” datastore may be designated as “hot” and synonyms therein may direct data to the second data structure.