0fd16cdac8ca_add_multi_label_support.py 文件源码

def downgrade():
    # ### commands auto generated by Alembic - please adjust! ###
    op.add_column('label_event', sa.Column('label', sa.VARCHAR(length=255), autoincrement=False, nullable=True))
    op.add_column('dataset', sa.Column('probability', postgresql.DOUBLE_PRECISION(precision=53), autoincrement=False, nullable=True))
    op.add_column('problem', sa.Column('label', sa.Unicode(length=255), nullable=True))

    op.execute('''
        UPDATE label_event SET label = (SELECT label FROM problem_label WHERE problem_label.id = label_event.label_id)
    ''')
    op.execute('''
        UPDATE dataset SET probability = (SELECT probability FROM dataset_label_probability WHERE dataset_label_probability.data_id = dataset.id)
    ''')
    op.execute('''
        UPDATE problem SET label = (SELECT label FROM problem_label WHERE problem_label.problem_id = problem.id)
    ''')

    op.alter_column('label_event', 'label', nullable=False)
    op.alter_column('problem', 'label', nullable=False)

    op.drop_column('problem', 'name')
    op.drop_index(op.f('ix_label_event_label_id'), table_name='label_event')
    op.drop_column('label_event', 'label_id')
    op.drop_index(op.f('ix_dataset_label_probability_label_id'), table_name='dataset_label_probability')
    op.drop_index(op.f('ix_dataset_label_probability_data_id'), table_name='dataset_label_probability')
    op.drop_table('dataset_label_probability')
    op.drop_table('problem_label')
    # ### end Alembic commands ###