fix: remove invalid child_id relationships from tag_parents (#1423)

* fix: remove invalid child_id relationships from tag_parents

* fix: use single statements in DB 102 & 202 migrations

* fix: remove unnecessary session.scalars() from migrations

docs/library-changes.md

@@ -193,3 +193,11 @@ Migration from the legacy JSON format is provided via a walkthrough when opening
 
 - Drops `type_key` columns from `text_fields` and `datetime_fields` tables.
 - Enforces column positions for `text_fields` and `datetime_fields` tables.
+
+#### Version 202
+
+| Added in Commit | Introduced in Release                                                   | Format |
+| --------------- | ----------------------------------------------------------------------- | ------ |
+|                 | [v9.6.1](https://github.com/TagStudioDev/TagStudio/releases/tag/v9.6.1) | SQLite |
+
+- Applies repairs to the `tag_parents` table, removing rows that reference child tags that have been deleted.

src/tagstudio/core/library/alchemy/constants.py

@@ -9,7 +9,7 @@ JSON_FILENAME: str = "ts_library.json"
 
 DB_VERSION_CURRENT_KEY: str = "CURRENT"
 DB_VERSION_INITIAL_KEY: str = "INITIAL"
-DB_VERSION: int = 201
+DB_VERSION: int = 202
 
 TAG_CHILDREN_QUERY = text("""
 WITH RECURSIVE ChildTags AS (

src/tagstudio/core/library/alchemy/library.py

@@ -571,12 +571,16 @@ class Library:
                     self.__apply_db103_migration(session)
                 if loaded_db_version < 104:
                     # changes: deletes preferences
-                    self.__apply_db104_migrations(session, library_dir)
+                    self.__apply_db104_migration(session, library_dir)
                 if loaded_db_version < 200:
-                    self.__apply_db200_migrations(session)
                     # changes: field tables
+                    self.__apply_db200_migration(session)
                 if initial_db_version < 200 and loaded_db_version < 201:
-                    self.__apply_db201_migrations(session)
+                    # changes: field tables
+                    self.__apply_db201_migration(session)
+                if loaded_db_version < 202:
+                    # changes: tag_parents
+                    self.__apply_db202_migration(session)
 
             session.execute(
                 text("CREATE INDEX IF NOT EXISTS idx_tags_name_shorthand ON tags (name, shorthand)")
@@ -719,8 +723,7 @@ class Library:
     def __apply_db102_migration(self, session: Session):
         """Migrate DB to DB_VERSION 102."""
         with session:
-            all_tag_ids = session.scalars(text("SELECT DISTINCT id FROM tags")).all()
-            stmt = delete(TagParent).where(TagParent.parent_id.not_in(all_tag_ids))
+            stmt = delete(TagParent).where(TagParent.parent_id.not_in(select(Tag.id).distinct()))
             session.execute(stmt)
             session.commit()
             logger.info("[Library][Migration] Verified TagParent table data")
@@ -754,7 +757,7 @@ class Library:
             )
             session.rollback()
 
-    def __apply_db104_migrations(self, session: Session, library_dir: Path):
+    def __apply_db104_migration(self, session: Session, library_dir: Path):
         """Migrate DB from DB_VERSION 103 to 104."""
         # Convert file extension list to ts_ignore file, if a .ts_ignore file does not exist
         self.__migrate_sql_to_ts_ignore(library_dir)
@@ -779,7 +782,7 @@ class Library:
         with open(ts_ignore, "w") as f:
             f.write(migrate_ext_list(extensions, is_exclude_list))
 
-    def __apply_db200_migrations(self, session: Session):
+    def __apply_db200_migration(self, session: Session):
         """Migrate DB to DB_VERSION 200."""
         with session:
             # Drop unused 'boolean_fields' and 'value_type' tables
@@ -866,7 +869,7 @@ class Library:
 
             session.commit()
 
-    def __apply_db201_migrations(self, session: Session):
+    def __apply_db201_migration(self, session: Session):
         """Migrate DB to DB_VERSION 201."""
         with session:
             create_text_fields_table = text("""
@@ -917,6 +920,14 @@ class Library:
 
             session.commit()
 
+    def __apply_db202_migration(self, session: Session):
+        """Migrate DB to DB_VERSION 202."""
+        with session:
+            stmt = delete(TagParent).where(TagParent.child_id.not_in(select(Tag.id).distinct()))
+            session.execute(stmt)
+            session.commit()
+            logger.info("[Library][Migration] Verified TagParent table data")
+
     @property
     def field_templates(self) -> Sequence[BaseFieldTemplate]:
         with Session(self.engine) as session: