Add index to FileDownload table on data obj id

nmdc_server/migrations/versions/c27777e272d3_add_file_download_data_obj_id_idx.py

@@ -0,0 +1,33 @@
+"""Add an index on `data_object_id` column of `file_download` table
+
+Speed up computing download counts for data objecsts.
+
+Revision ID: c27777e272d3
+Revises: 6e6dec0daa7c
+Create Date: 2025-02-28 20:38:34.018502
+
+"""
+
+from typing import Optional
+
+from alembic import op
+
+# revision identifiers, used by Alembic.
+revision: str = "c27777e272d3"
+down_revision: Optional[str] = "6e6dec0daa7c"
+branch_labels: Optional[str] = None
+depends_on: Optional[str] = None
+
+
+def upgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.create_index(
+        op.f("ix_file_download_data_object_id"), "file_download", ["data_object_id"], unique=False
+    )
+    # ### end Alembic commands ###
+
+
+def downgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_index(op.f("ix_file_download_data_object_id"), table_name="file_download")
+    # ### end Alembic commands ###

nmdc_server/models.py

@@ -750,7 +750,7 @@ class FileDownload(Base):
 
     id = Column(UUID(as_uuid=True), primary_key=True, default=uuid4)
     created = Column(DateTime, nullable=False, default=datetime.utcnow)
-    data_object_id = Column(String, ForeignKey("data_object.id"), nullable=False)
+    data_object_id = Column(String, ForeignKey("data_object.id"), nullable=False, index=True)
     ip = Column(String, nullable=False)
     user_agent = Column(String, nullable=True)
     orcid = Column(String, nullable=False)