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Forked from utek/Exclude_tables.md
Last active June 4, 2020 23:28
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Define ignored tables in alembic.ini

Add this in your ini file:

[alembic:exclude]
tables = spatial_ref_sys

In env.py:

def exclude_tables_from_config(config_):
    tables_ = config_.get("tables", None)
    if tables_ is not None:
        tables = tables_.split(",")
    return tables

exclude_tables = exclude_tables_from_config(config.get_section('alembic:exclude'))


def include_object(object, name, type_, reflected, compare_to):    
    if type_ == "table" and name in exclude_tables:
        return False
    else:
        return True

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.

    """
    # url = config.get_main_option("sqlalchemy.url")
    context.configure(url=engine.url, include_object=include_object)

    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.

    """
    if isinstance(engine, Engine):
        connection = engine.connect()
    else:
        raise Exception('Expected engine instance got %s instead' % type(engine))

    context.configure(
        connection=connection,
        target_metadata=target_metadata,
        include_object=include_object
    )

    try:
        with context.begin_transaction():
            context.run_migrations()
    finally:
        connection.close()

Alternative way:

def include_object(object, name, type_, reflected, compare_to):    
    if type_ == "table" and name == 'spatial_ref_sys':
        return False
    else:
        return True

def run_migrations_offline():
    #[…]
    context.configure(# whatever generated params already exist, then
                      include_object=include_object)
    # […]
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