added migration plan

backend/open_webui/migrations/versions/20250619_add_indexes_for_performance.py

@@ -0,0 +1,57 @@
+"""Add performance indexes to chat, tag, and function tables
+
+---
+Database Indexing & Migration Instructions
+------------------------------------------
+Open-WebUI now automatically creates indexes on key columns in the `chat`, `tag`, and `function` tables for improved performance with SQLite and PostgreSQL.
+
+**For existing installations:**
+Apply this migration to add the new indexes to your database:
+
+    alembic upgrade head
+
+This will significantly speed up filtering, sorting, and joining operations as your data grows.
+---
+
+Revision ID: 20250619_add_indexes
+Revises:
+Create Date: 2025-06-19
+
+"""
+
+from alembic import op
+import sqlalchemy as sa
+
+# revision identifiers, used by Alembic.
+revision = '20250619_add_indexes'
+down_revision = None
+branch_labels = None
+depends_on = None
+
+def upgrade():
+    # Chat table indexes
+    op.create_index('folder_id_idx', 'chat', ['folder_id'])
+    op.create_index('user_id_pinned_idx', 'chat', ['user_id', 'pinned'])
+    op.create_index('user_id_archived_idx', 'chat', ['user_id', 'archived'])
+    op.create_index('updated_at_user_id_idx', 'chat', ['updated_at', 'user_id'])
+    op.create_index('folder_id_user_id_idx', 'chat', ['folder_id', 'user_id'])
+
+    # Tag table index
+    op.create_index('user_id_idx', 'tag', ['user_id'])
+
+    # Function table index
+    op.create_index('is_global_idx', 'function', ['is_global'])
+
+def downgrade():
+    # Chat table indexes
+    op.drop_index('folder_id_idx', table_name='chat')
+    op.drop_index('user_id_pinned_idx', table_name='chat')
+    op.drop_index('user_id_archived_idx', table_name='chat')
+    op.drop_index('updated_at_user_id_idx', table_name='chat')
+    op.drop_index('folder_id_user_id_idx', table_name='chat')
+
+    # Tag table index
+    op.drop_index('user_id_idx', table_name='tag')
+
+    # Function table index
+    op.drop_index('is_global_idx', table_name='function')