**** CubicPower OpenStack Study ****
def upgrade(migrate_engine):
meta = sql.MetaData()
meta.bind = migrate_engine
role_table = sql.Table('role', meta, autoload=True)
# name should be 255 characters to match fresh database
role_table.c.name.alter(type=sql.String(length=255))
# blank 'extra' field should be "{}"
none = None
update = role_table.update().where(role_table.c.extra == none).values(
{role_table.c.extra: "{}"})
migrate_engine.execute(update)
**** CubicPower OpenStack Study ****
def downgrade(migrate_engine):
# this fixes bugs in migration 001 and 007 that result in discrepancies
# between fresh databases and databases updated from 004 (folsom).
# the changes fixing 007 will be rolled back in 007's rollback if
# the user desires to return to a state before the existence of the extra
# column.
# the name length change reflects the current default and should not be
# rolled back.
pass