def run_migrations_offline():
"""Run migrations in 'offline' mode.
This configures the context with just a URL
and not an Engine, though an Engine is acceptable
here as well. By skipping the Engine creation
we don't even need a DBAPI to be available.
Calls to context.execute() here emit the given string to the
script output.
"""
context.configure(url=db_uri())
with context.begin_transaction():
context.run_migrations()
def run_migrations_online():
"""Run migrations in 'online' mode.
In this scenario we need to create an Engine
and associate a connection with the context.
"""
engine = create_engine(db_uri(), poolclass=pool.NullPool)
connection = engine.connect()
context.configure(
connection=connection,
target_metadata=target_metadata
)
try:
with context.begin_transaction():
context.run_migrations()
finally:
connection.close()
