reduce to 1 object per asset

backend/migrations/202511120000_collapse_asset_objects/down.sql

@@ -0,0 +1,24 @@
+CREATE TABLE tenant.document_asset_objects (
+    id UUID PRIMARY KEY,
+    asset_id UUID NOT NULL REFERENCES tenant.document_assets(id) ON DELETE CASCADE,
+    ordinal INT NOT NULL,
+    s3_key TEXT NOT NULL,
+    metadata JSONB NOT NULL DEFAULT '{}'::jsonb,
+    tenant_id UUID NOT NULL REFERENCES shared.tenants(id),
+    CONSTRAINT document_asset_objects_ordinal_positive CHECK (ordinal >= 1),
+    CONSTRAINT document_asset_objects_asset_ordinal_unique UNIQUE (asset_id, ordinal)
+);
+
+CREATE INDEX idx_document_asset_objects_asset_ordinal
+    ON tenant.document_asset_objects(asset_id, ordinal);
+
+CREATE INDEX document_asset_objects_tenant_id_idx ON tenant.document_asset_objects(tenant_id);
+
+ALTER TABLE tenant.document_assets ADD COLUMN cardinality INT;
+UPDATE tenant.document_assets SET cardinality = 1;
+
+INSERT INTO tenant.document_asset_objects (id, asset_id, ordinal, s3_key, metadata, tenant_id)
+SELECT gen_random_uuid(), id, 1, s3_key, metadata, tenant_id
+FROM tenant.document_assets;
+
+ALTER TABLE tenant.document_assets DROP COLUMN s3_key;

backend/migrations/202511120000_collapse_asset_objects/up.sql

@@ -0,0 +1,27 @@
+-- Prevent concurrent inserts/updates during backfill.
+LOCK TABLE tenant.document_asset_objects IN ACCESS EXCLUSIVE MODE;
+LOCK TABLE tenant.document_assets IN ACCESS EXCLUSIVE MODE;
+
+ALTER TABLE tenant.document_assets ADD COLUMN s3_key TEXT;
+
+UPDATE tenant.document_assets AS da
+SET s3_key = o.s3_key,
+    metadata = COALESCE(da.metadata, '{}'::jsonb) || COALESCE(o.metadata, '{}'::jsonb)
+FROM tenant.document_asset_objects AS o
+WHERE o.asset_id = da.id
+  AND o.ordinal = 1;
+
+DELETE FROM tenant.document_asset_objects WHERE ordinal <> 1;
+
+DO $$
+BEGIN
+    IF EXISTS (SELECT 1 FROM tenant.document_assets WHERE s3_key IS NULL) THEN
+        RAISE EXCEPTION 'cannot drop document_asset_objects: some assets are missing a populated ordinal 1 object (s3_key null)';
+    END IF;
+END
+$$;
+
+ALTER TABLE tenant.document_assets ALTER COLUMN s3_key SET NOT NULL;
+ALTER TABLE tenant.document_assets DROP COLUMN cardinality;
+
+DROP TABLE tenant.document_asset_objects;