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  1. Glossary
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  3. Schema Migrations
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  5. Expand / Contract Pattern

Expand / Contract Pattern

Schema MigrationsOpen Source

A two-phase migration strategy: Expand adds the new schema elements alongside the old ones. Contract removes the old elements after all applications have migrated to the new schema. Enables zero-downtime changes.

Related terms

Zero-Downtime Migrationpgroll
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