diff --git a/acacore/database/upgrade.py b/acacore/database/upgrade.py
index c9cedeb..a2e34f4 100644
--- a/acacore/database/upgrade.py
+++ b/acacore/database/upgrade.py
@@ -220,7 +220,7 @@ def upgrade_3_2to3_3(conn: Connection) -> Version:
     if not conn.execute("select 1 from pragma_table_info('Files') where name = 'original_name'").fetchone():
         conn.execute("alter table Files add column original_name text not null default ''")
     if not conn.execute("select 1 from pragma_table_info('Files') where name = 'processed_name'").fetchone():
-        conn.execute("alter table Files add column processed_name text default null")
+        conn.execute("alter table Files add column processed_name text default '[]'")
 
     def _find_original_name(uuid: str, relative_path: str) -> str:
         original_path: Path = Path(relative_path)
diff --git a/acacore/models/file.py b/acacore/models/file.py
index 737d1be..9675651 100644
--- a/acacore/models/file.py
+++ b/acacore/models/file.py
@@ -91,7 +91,7 @@ class File(BaseModel):
     processed: bool = False
     lock: bool = False
     original_name: str
-    processed_name: str | None = None
+    processed_names: list[str] = Field(default_factory=list)
     root: Path | None = DBField(None, ignore=True)
 
     # noinspection PyNestedDecorators