One-time migration from the old Python/Flask Tanabata DB into the new
core/data/acl/activity schema.
- transform.sql: reads a `legacy` schema and writes the new one in a single,
idempotent transaction. Remaps user/mime ids (uuid -> smallint by name),
inverts is_private -> is_public, lifts EXIF out of files.metadata into the
exif column, preserves pool hierarchy/created under metadata, synthesises
file_pool ordering, derives acl object types, sanitises colors/notes.
- migrate.sh: links the new DB to the old one via postgres_fdw, imports the
old public schema as `legacy`, runs the transform, tears the link down.
- README.md: mapping table, decisions/lossy points, and the separate
physical-blob copy step.
- docs/reference/schema.sql: the old DB schema the migration is built from
(referenced by the README).
Verified end-to-end on PostgreSQL 16 (synthetic legacy data, all
transformations and idempotency checked).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
