회기 연속성과 멀티 케이스 계약을 영속화

infra/db/init/22_case_profile_multi_case.sql

@@ -0,0 +1,129 @@
+-- =============================================================================
+-- Vignette · migration 22 — 동일 learner-persona의 새 사례 분리
+-- =============================================================================
+-- migration 21의 learner-persona 단일 활성 회기 제약은 그대로 유지한다.
+-- 이 migration은 끝난 기존 사례를 보존한 채, 같은 내담자에 새 사례(case_profile)를
+-- 만들 수 있도록 legacy pair unique만 제거한다. raw transcript·memory row는 수정하지 않는다.
+--
+-- CREATE INDEX CONCURRENTLY는 transaction block 안에서 실행할 수 없다.
+-- release agent가 online migration으로 owner psql에 전달한다.
+
+SET lock_timeout = '5s';
+SET statement_timeout = '15min';
+
+DO $$
+DECLARE
+  legacy_constraints text[];
+  target_index oid := to_regclass('app.idx_case_profile_learner_persona_activity');
+BEGIN
+  SELECT array_agg(candidate.conname ORDER BY candidate.conname)
+  INTO legacy_constraints
+  FROM (
+    SELECT constraint_meta.conname
+    FROM pg_constraint AS constraint_meta
+    WHERE constraint_meta.conrelid = 'app.case_profile'::regclass
+      AND constraint_meta.contype = 'u'
+      AND ARRAY(
+        SELECT attribute_meta.attname
+        FROM unnest(constraint_meta.conkey) WITH ORDINALITY AS key_column(attnum, ordinality)
+        JOIN pg_attribute AS attribute_meta
+          ON attribute_meta.attrelid = constraint_meta.conrelid
+         AND attribute_meta.attnum = key_column.attnum
+        ORDER BY key_column.ordinality
+      ) = ARRAY['persona_id', 'learner_id']::text[]
+  ) AS candidate;
+
+  IF COALESCE(array_length(legacy_constraints, 1), 0) > 1 THEN
+    RAISE EXCEPTION
+      'migration 22 blocked: multiple legacy case_profile persona-learner unique constraints exist';
+  END IF;
+
+  IF target_index IS NOT NULL AND NOT EXISTS (
+    SELECT 1
+    FROM pg_index AS index_meta
+    WHERE index_meta.indexrelid = target_index
+      AND index_meta.indrelid = 'app.case_profile'::regclass
+      AND index_meta.indisvalid
+      AND index_meta.indisready
+      AND NOT index_meta.indisunique
+      AND index_meta.indnkeyatts = 4
+      AND pg_get_indexdef(index_meta.indexrelid) LIKE
+        '%(learner_id, persona_id, updated_at DESC, case_id)%'
+  ) THEN
+    RAISE EXCEPTION
+      'migration 22 blocked: target index exists but is invalid or has a different definition';
+  END IF;
+END
+$$;
+
+CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_case_profile_learner_persona_activity
+  ON app.case_profile (learner_id, persona_id, updated_at DESC, case_id);
+
+DO $$
+DECLARE
+  legacy_constraints text[];
+BEGIN
+  IF NOT EXISTS (
+    SELECT 1
+    FROM pg_index AS index_meta
+    WHERE index_meta.indexrelid = 'app.idx_case_profile_learner_persona_activity'::regclass
+      AND index_meta.indrelid = 'app.case_profile'::regclass
+      AND index_meta.indisvalid
+      AND index_meta.indisready
+      AND NOT index_meta.indisunique
+      AND index_meta.indnkeyatts = 4
+      AND pg_get_indexdef(index_meta.indexrelid) LIKE
+        '%(learner_id, persona_id, updated_at DESC, case_id)%'
+  ) THEN
+    RAISE EXCEPTION
+      'migration 22 failed: valid case activity index was not created';
+  END IF;
+
+  SELECT array_agg(candidate.conname ORDER BY candidate.conname)
+  INTO legacy_constraints
+  FROM (
+    SELECT constraint_meta.conname
+    FROM pg_constraint AS constraint_meta
+    WHERE constraint_meta.conrelid = 'app.case_profile'::regclass
+      AND constraint_meta.contype = 'u'
+      AND ARRAY(
+        SELECT attribute_meta.attname
+        FROM unnest(constraint_meta.conkey) WITH ORDINALITY AS key_column(attnum, ordinality)
+        JOIN pg_attribute AS attribute_meta
+          ON attribute_meta.attrelid = constraint_meta.conrelid
+         AND attribute_meta.attnum = key_column.attnum
+        ORDER BY key_column.ordinality
+      ) = ARRAY['persona_id', 'learner_id']::text[]
+  ) AS candidate;
+
+  IF COALESCE(array_length(legacy_constraints, 1), 0) > 1 THEN
+    RAISE EXCEPTION
+      'migration 22 blocked: multiple legacy case_profile persona-learner unique constraints exist';
+  END IF;
+
+  IF COALESCE(array_length(legacy_constraints, 1), 0) = 1 THEN
+    EXECUTE format(
+      'ALTER TABLE app.case_profile DROP CONSTRAINT %I',
+      legacy_constraints[1]
+    );
+  END IF;
+
+  IF EXISTS (
+    SELECT 1
+    FROM pg_constraint AS constraint_meta
+    WHERE constraint_meta.conrelid = 'app.case_profile'::regclass
+      AND constraint_meta.contype = 'u'
+      AND ARRAY(
+        SELECT attribute_meta.attname
+        FROM unnest(constraint_meta.conkey) WITH ORDINALITY AS key_column(attnum, ordinality)
+        JOIN pg_attribute AS attribute_meta
+          ON attribute_meta.attrelid = constraint_meta.conrelid
+         AND attribute_meta.attnum = key_column.attnum
+        ORDER BY key_column.ordinality
+      ) = ARRAY['persona_id', 'learner_id']::text[]
+  ) THEN
+    RAISE EXCEPTION
+      'migration 22 failed: legacy case_profile persona-learner unique constraint remains';
+  END IF;
+END
+$$;