glm-5.1
67ccfbf928
- Create decisions/ directory with 32 numbered ADRs (ADR-001 through ADR-032) extracted from inline DD/SD/ED/SE decision sections - Create open-questions.md with 16 OQs organized by theme, cross-referenced to ADRs, with status tracking (resolved/open) - Create README.md as architecture index with doc table, ADR table, and lifecycle status definitions (draft/reviewed/stable/deprecated) - Replace inline decision sections in all spec docs with ADR reference tables - Replace inline open questions with OQ references to centralized tracker - Update frontmatter: metagraph-module.md, overview.md, sqlite-host.md → reviewed; schema-evolution.md and encrypted-data.md remain draft - DD1-DD10 → ADR-009 through ADR-018 - D1-D8 → ADR-001 through ADR-008 - SD1-SD5 → ADR-019 through ADR-023 (SD5 folded into ADR-006/008) - ED1-ED5 → ADR-023 through ADR-027 - SE1-SE5 → ADR-028 through ADR-032
24 lines
1.0 KiB
Markdown
24 lines
1.0 KiB
Markdown
# ADR-028: Additive-only for v1, Cast migration when needed
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## Status
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Accepted
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## Context
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Graph type schemas will evolve over time. Changes range from adding optional fields (non-breaking) to removing fields or changing types (breaking). The repository layer needs a strategy for handling schema changes.
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## Decision
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For v1, schema changes should be additive (new optional fields, new types, new enum values). This avoids data migration entirely. When additive-only is insufficient, `Value.Cast` handles common migration cases (adding fields with defaults, type narrowing). Custom migration functions are the consumer's responsibility for breaking changes.
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## Consequences
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- v1 schemas should only add optional fields and new types
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- The `version` field on `graph_types` stays at 1 for additive changes
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- Breaking changes require a version bump and migration strategy
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- `Value.Cast` is available for common migration cases but is not a migration framework
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## References
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- [schema-evolution.md](../schema-evolution.md) |