use cached prompt generation (#768)

Co-authored-by: Shuchang Zheng <wintonzheng0325@gmail.com>

alembic/versions/2024_09_03_0356-0de9150bc624_update_task_generation_table_use_user_.py

@@ -0,0 +1,46 @@
+"""update task_generation table - use user_prompt_hash as the index of a user prompt
+
+Revision ID: 0de9150bc624
+Revises: 6de11b2be7c8
+Create Date: 2024-09-03 03:56:58.352307+00:00
+
+"""
+
+from typing import Sequence, Union
+
+import sqlalchemy as sa
+
+from alembic import op
+
+# revision identifiers, used by Alembic.
+revision: str = "0de9150bc624"
+down_revision: Union[str, None] = "6de11b2be7c8"
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.add_column("task_generations", sa.Column("user_prompt_hash", sa.String(), nullable=True))
+    op.add_column("task_generations", sa.Column("source_task_generation_id", sa.String(), nullable=True))
+    op.drop_index("ix_task_generations_user_prompt", table_name="task_generations")
+    op.create_index(
+        op.f("ix_task_generations_source_task_generation_id"),
+        "task_generations",
+        ["source_task_generation_id"],
+        unique=False,
+    )
+    op.create_index(
+        op.f("ix_task_generations_user_prompt_hash"), "task_generations", ["user_prompt_hash"], unique=False
+    )
+    # ### end Alembic commands ###
+
+
+def downgrade() -> None:
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_index(op.f("ix_task_generations_user_prompt_hash"), table_name="task_generations")
+    op.drop_index(op.f("ix_task_generations_source_task_generation_id"), table_name="task_generations")
+    op.create_index("ix_task_generations_user_prompt", "task_generations", ["user_prompt"], unique=False)
+    op.drop_column("task_generations", "source_task_generation_id")
+    op.drop_column("task_generations", "user_prompt_hash")
+    # ### end Alembic commands ###