[add] migration script

api/migrations/versions/4bf27c66ae63_202602281918.py

@@ -0,0 +1,44 @@
+"""202602281918
+
+Revision ID: 4bf27c66ae63
+Revises: 7672d8f0f939
+Create Date: 2026-02-28 19:18:38.332468
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision: str = '4bf27c66ae63'
+down_revision: Union[str, None] = '7672d8f0f939'
+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! ###
+    # Add columns as nullable first
+    op.add_column('ontology_class', sa.Column('is_system_default', sa.Boolean(), nullable=True, comment='是否为系统默认类型'))
+    op.add_column('ontology_scene', sa.Column('is_system_default', sa.Boolean(), nullable=True, comment='是否为系统默认场景'))
+    
+    # Set default value for existing rows
+    op.execute("UPDATE ontology_class SET is_system_default = false WHERE is_system_default IS NULL")
+    op.execute("UPDATE ontology_scene SET is_system_default = false WHERE is_system_default IS NULL")
+    
+    # Now make columns NOT NULL
+    op.alter_column('ontology_class', 'is_system_default', nullable=False)
+    op.alter_column('ontology_scene', 'is_system_default', nullable=False)
+    
+    op.create_index(op.f('ix_ontology_scene_is_system_default'), 'ontology_scene', ['is_system_default'], unique=False)
+    # ### end Alembic commands ###
+
+
+def downgrade() -> None:
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_index(op.f('ix_ontology_scene_is_system_default'), table_name='ontology_scene')
+    op.drop_column('ontology_scene', 'is_system_default')
+    op.drop_column('ontology_class', 'is_system_default')
+    # ### end Alembic commands ###