文件版本管理-初步优化

backend/app/models/audit_log.py

@@ -1,7 +1,7 @@
 import uuid
 from datetime import datetime
 
-from sqlalchemy import DateTime, ForeignKey, String, Text, func
+from sqlalchemy import DateTime, ForeignKey, Index, String, Text, func
 from sqlalchemy.dialects.postgresql import UUID
 from sqlalchemy.orm import Mapped, mapped_column
 
@@ -10,6 +10,7 @@ from app.db.base_class import Base
 
 class AuditLog(Base):
     __tablename__ = "audit_logs"
+    __table_args__ = (Index("ix_audit_logs_entity_at", "entity_type", "entity_id", "created_at"),)
 
     id: Mapped[uuid.UUID] = mapped_column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
     study_id: Mapped[uuid.UUID | None] = mapped_column(UUID(as_uuid=True), ForeignKey("studies.id"), nullable=True)