parent_object_id was never written or read by any application code (verified via repo-wide grep: only the baseline migration and the ORM model referenced it). The orphan index idx_storage_parent likewise served nothing. Tree structure is maintained entirely via the materialized path in storage_objects.relative_path (LIKE-prefix queries in backend/src/backend/scripts.py: list_workspace_tree, list_workspace_directories). The column mislead a prior review into proposing an adjacency-list table — removing it eliminates that temptation for the next reader. Migration: migrations/versions/f7a8b9c0d1e2_drop_storage_parent.py - Drops idx_storage_parent first, then parent_object_id (correct order on MySQL). - MySQL 8.0 has no IF EXISTS on DROP INDEX / DROP COLUMN, so calls are unconditional. - Updates the storage_objects TABLE COMMENT so the materialized-path warning reaches the DB, not just the ORM (Codex review finding). - Downgrade restores both. Model: common/src/common/db/models/storage.py - Removes the dead Index entry and the dead column. - Refreshes the table comment to flag the materialized-path contract. Verified: - alembic upgrade head: applied, head = f7a8b9c0d1e2 - SHOW INDEX / SHOW COLUMNS: 0 rows - TABLE COMMENT updated in information_schema - pytest backend/tests: 43 passed
Migration Revisions
该目录只保存经过评审和验证的 Alembic 迁移版本。
- 已发布迁移不得直接修改。
- 新迁移必须同时提供可执行的
upgrade()和downgrade()。 - 自动生成后必须检查数据类型、约束、索引和执行顺序。
Migration Revisions
该目录只保存经过评审和验证的 Alembic 迁移版本。
Baseline
e1f2a3b4c5d6_rebuild_baseline.py— 2026-08-14 重建的基线迁移,包含完整 schema + seed。- 之前的 8 个迁移文件已合并并删除;新环境从此基线开始。
Rules
- 已发布迁移不得直接修改。
- 新迁移必须同时提供可执行的
upgrade()和downgrade()。 - 自动生成后必须检查数据类型、约束、索引和执行顺序。