old_contents: """empty message
  
  Revision ID: 40e8fc359768
  Revises: 3d569239043f
  Create Date: 2014-03-14 23:58:52.158538
  
  """
  
  # revision identifiers, used by Alembic.
  revision = '40e8fc359768'
  down_revision = '26dfc02ce3ff'
  
  from alembic import op
  import sqlalchemy as sa
  
  
  def upgrade():
      ### commands auto generated by Alembic - please adjust! ###
      op.add_column('node', sa.Column('parent_node_id', sa.Integer(), nullable=True))
      op.create_index('ix_node_parent_node_id', 'node', ['parent_node_id'], unique=False)
      op.create_unique_constraint('uc_user_read_topic', 'read_topic', ['user_id', 'topic_id'])
      ### end Alembic commands ###
  
  
  def downgrade():
      ### commands auto generated by Alembic - please adjust! ###
      op.drop_constraint('uc_user_read_topic', 'read_topic')
      op.drop_index('ix_node_parent_node_id', table_name='node')
      op.drop_column('node', 'parent_node_id')
      ### end Alembic commands ###
  
new_contents: """empty message
  
  Revision ID: 40e8fc359768
  Revises: 3d569239043f
  Create Date: 2014-03-14 23:58:52.158538
  
  """
  
  # revision identifiers, used by Alembic.
  revision = '40e8fc359768'
  down_revision = '276f5d7b1612'
  
  from alembic import op
  import sqlalchemy as sa
  
  
  def upgrade():
      ### commands auto generated by Alembic - please adjust! ###
      op.add_column('node', sa.Column('parent_node_id', sa.Integer(), nullable=True))
      op.create_index('ix_node_parent_node_id', 'node', ['parent_node_id'], unique=False)
      op.create_unique_constraint('uc_user_read_topic', 'read_topic', ['user_id', 'topic_id'])
      ### end Alembic commands ###
  
  
  def downgrade():
      ### commands auto generated by Alembic - please adjust! ###
      op.drop_constraint('uc_user_read_topic', 'read_topic')
      op.drop_index('ix_node_parent_node_id', table_name='node')
      op.drop_column('node', 'parent_node_id')
      ### end Alembic commands ###
  
subject: Fix migration script again