feat(education): complete Flyway migration and atomic submit

sql/postgresql/education/009-education-idempotency-unified.sql

@@ -0,0 +1,103 @@
+-- =============================================
+-- Education 模块 — 统一幂等表 DDL (PostgreSQL)
+-- Ticket: 合并 Answer + Submit 幂等表为统一 education_idempotency
+-- Migration: 009
+-- Prerequisites: 002-education-practice-session.sql
+-- =============================================
+
+-- =============================================
+-- Preconditions
+-- =============================================
+-- Verify table does not already exist:
+--   SELECT COUNT(*) FROM information_schema.tables
+--     WHERE table_catalog = current_database()
+--       AND table_name = 'education_idempotency';
+-- Result MUST be 0 before executing this migration.
+--
+-- NOTE: This table replaces education_answer_idempotency and education_submit_idempotency.
+-- Those tables should be dropped after this migration is verified:
+--   DROP TABLE IF EXISTS education_answer_idempotency;
+--   DROP TABLE IF EXISTS education_submit_idempotency;
+
+-- =============================================
+-- 统一幂等表
+-- =============================================
+-- Purpose: Unified idempotency store for all education write operations.
+--   operation field distinguishes: SUBMIT_ANSWER vs SUBMIT_SESSION.
+--   Same (tenant, user, operation, idempotency_key) + same request_hash → replay original response.
+--   Same key + different request_hash → conflict.
+--   PostgreSQL ON CONFLICT DO NOTHING resolves concurrent same-key inserts.
+--
+-- Indexes:
+--   uk_idempotency — per-tenant, per-actor, per-operation uniqueness for idempotency key.
+--     Used by: IdempotencyStoreMapper.insertIgnore() ON CONFLICT resolution.
+--   idx_tenant_session — covers lookup by session for audit/debug.
+--
+-- Fields specific to SUBMIT_ANSWER: question_id, selected_answer (nullable for SUBMIT_SESSION).
+-- Fields specific to SUBMIT_SESSION: report_id (nullable for SUBMIT_ANSWER).
+-- response_json: stores serialized response for replay after timeout/retry.
+-- request_hash: SHA-256 of canonical payload for content-based dedup.
+CREATE TABLE education_idempotency (
+    id               BIGINT       GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    tenant_id        BIGINT       NOT NULL,
+    user_id          BIGINT       NOT NULL,
+    operation        VARCHAR(32)  NOT NULL,
+    idempotency_key  VARCHAR(64)  NOT NULL,
+    request_hash     VARCHAR(64)  NOT NULL,
+    session_id       BIGINT       NOT NULL,
+    question_id      VARCHAR(64)  DEFAULT NULL,
+    selected_answer  TEXT         DEFAULT NULL,
+    report_id        BIGINT       DEFAULT NULL,
+    status           VARCHAR(20)  NOT NULL DEFAULT 'ACCEPTED',
+    response_json    TEXT         DEFAULT NULL,
+    business_payload JSONB        DEFAULT NULL,
+    creator          VARCHAR(64)  DEFAULT '',
+    create_time      TIMESTAMP    NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updater          VARCHAR(64)  DEFAULT '',
+    update_time      TIMESTAMP    NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    deleted          BOOLEAN      NOT NULL DEFAULT false
+);
+
+COMMENT ON TABLE education_idempotency IS '教育-统一幂等记录（合并 answer + submit）';
+COMMENT ON COLUMN education_idempotency.id IS '主键';
+COMMENT ON COLUMN education_idempotency.tenant_id IS '租户编号';
+COMMENT ON COLUMN education_idempotency.user_id IS '用户编号';
+COMMENT ON COLUMN education_idempotency.operation IS '操作类型：SUBMIT_ANSWER-答题, SUBMIT_SESSION-交卷';
+COMMENT ON COLUMN education_idempotency.idempotency_key IS '客户端幂等键（UUID）';
+COMMENT ON COLUMN education_idempotency.request_hash IS '请求载荷 SHA-256 哈希';
+COMMENT ON COLUMN education_idempotency.session_id IS '会话 ID';
+COMMENT ON COLUMN education_idempotency.question_id IS '题目 ID（SUBMIT_ANSWER）';
+COMMENT ON COLUMN education_idempotency.selected_answer IS '学生已选答案（SUBMIT_ANSWER）';
+COMMENT ON COLUMN education_idempotency.report_id IS '关联报告 ID（SUBMIT_SESSION）';
+COMMENT ON COLUMN education_idempotency.status IS '状态：ACCEPTED-已接受, CONFLICT-冲突';
+COMMENT ON COLUMN education_idempotency.response_json IS '首次成功响应 JSON（用于重试重放）';
+COMMENT ON COLUMN education_idempotency.business_payload IS '业务扩展载荷（JSONB）';
+COMMENT ON COLUMN education_idempotency.creator IS '创建者';
+COMMENT ON COLUMN education_idempotency.create_time IS '创建时间';
+COMMENT ON COLUMN education_idempotency.updater IS '更新者';
+COMMENT ON COLUMN education_idempotency.update_time IS '更新时间';
+COMMENT ON COLUMN education_idempotency.deleted IS '是否删除';
+
+CREATE UNIQUE INDEX uk_idempotency ON education_idempotency (tenant_id, user_id, operation, idempotency_key);
+CREATE INDEX idx_idempotency_tenant_session ON education_idempotency (tenant_id, session_id);
+
+-- =============================================
+-- PracticeSessionDO: add review_fingerprint column
+-- =============================================
+-- Purpose: Store canonical fingerprint for wrong-question review session idempotency.
+--   SHA-256 of comma-joined sorted wrong_question IDs for deterministic comparison.
+ALTER TABLE education_practice_session
+    ADD COLUMN review_fingerprint VARCHAR(64) DEFAULT NULL;
+
+COMMENT ON COLUMN education_practice_session.review_fingerprint IS '错题复习指纹（SHA-256），用于幂等创建';
+
+-- =============================================
+-- Post-migration verification queries
+-- =============================================
+-- Verify new table exists:
+--   \d education_idempotency
+-- Verify unique index:
+--   SELECT * FROM pg_indexes WHERE tablename = 'education_idempotency';
+-- Verify column added:
+--   SELECT column_name, data_type FROM information_schema.columns
+--    WHERE table_name = 'education_practice_session' AND column_name = 'review_fingerprint';