add index to speed up get last attempt (#3636)

* add index to speed up get last attempt

* use descending order

* put back unique param

* how did this not get formatted?

---------

Co-authored-by: Richard Kuo (Danswer) <rkuo@onyx.app>

backend/alembic/versions/369644546676_add_composite_index_for_index_attempt_.py

@@ -0,0 +1,35 @@
+"""add composite index for index attempt time updated
+
+Revision ID: 369644546676
+Revises: 2955778aa44c
+Create Date: 2025-01-08 15:38:17.224380
+
+"""
+from alembic import op
+from sqlalchemy import text
+
+# revision identifiers, used by Alembic.
+revision = "369644546676"
+down_revision = "2955778aa44c"
+branch_labels: None = None
+depends_on: None = None
+
+
+def upgrade() -> None:
+    op.create_index(
+        "ix_index_attempt_ccpair_search_settings_time_updated",
+        "index_attempt",
+        [
+            "connector_credential_pair_id",
+            "search_settings_id",
+            text("time_updated DESC"),
+        ],
+        unique=False,
+    )
+
+
+def downgrade() -> None:
+    op.drop_index(
+        "ix_index_attempt_ccpair_search_settings_time_updated",
+        table_name="index_attempt",
+    )

backend/onyx/db/models.py

@@ -18,6 +18,7 @@ from fastapi_users_db_sqlalchemy.access_token import SQLAlchemyBaseAccessTokenTa
 from fastapi_users_db_sqlalchemy.generics import TIMESTAMPAware
 from sqlalchemy import Boolean
 from sqlalchemy import DateTime
+from sqlalchemy import desc
 from sqlalchemy import Enum
 from sqlalchemy import Float
 from sqlalchemy import ForeignKey
@@ -813,6 +814,13 @@ class IndexAttempt(Base):
             "connector_credential_pair_id",
             "time_created",
         ),
+        Index(
+            "ix_index_attempt_ccpair_search_settings_time_updated",
+            "connector_credential_pair_id",
+            "search_settings_id",
+            desc("time_updated"),
+            unique=False,
+        ),
     )
 
     def __repr__(self) -> str: