Method __init__

lib/sqlalchemy/sql/schema.py:5816–5951

Create a new MetaData object. :param schema: The default schema to use for the :class:`_schema.Table`, :class:`.Sequence`, and potentially other objects associated with this :class:`_schema.MetaData`. Defaults to ``None``. .. seealso::

(
        self,
        schema: Optional[str] = None,
        quote_schema: Optional[bool] = None,
        naming_convention: Optional[_NamingSchemaParameter] = None,
        info: Optional[_InfoType] = None,
    )

    __visit_name__ = "metadata"

    def __init__(
        self,
        schema: Optional[str] = None,
        quote_schema: Optional[bool] = None,
        naming_convention: Optional[_NamingSchemaParameter] = None,
        info: Optional[_InfoType] = None,
    ) -> None:
        """Create a new MetaData object.

        :param schema:
           The default schema to use for the :class:`_schema.Table`,
           :class:`.Sequence`, and potentially other objects associated with
           this :class:`_schema.MetaData`. Defaults to ``None``.

           .. seealso::

                :ref:`schema_metadata_schema_name` - details on how the
                :paramref:`_schema.MetaData.schema` parameter is used.

                :paramref:`_schema.Table.schema`

                :paramref:`.Sequence.schema`

        :param quote_schema:
            Sets the ``quote_schema`` flag for those :class:`_schema.Table`,
            :class:`.Sequence`, and other objects which make usage of the
            local ``schema`` name.

        :param info: Optional data dictionary which will be populated into the
            :attr:`.SchemaItem.info` attribute of this object.

        :param naming_convention: a dictionary referring to values which
          will establish default naming conventions for :class:`.Constraint`
          and :class:`.Index` objects, for those objects which are not given
          a name explicitly.

          The keys of this dictionary may be:

          * a constraint or Index class, e.g. the :class:`.UniqueConstraint`,
            :class:`_schema.ForeignKeyConstraint` class, the :class:`.Index`
            class

          * a string mnemonic for one of the known constraint classes;
            ``"fk"``, ``"pk"``, ``"ix"``, ``"ck"``, ``"uq"`` for foreign key,
            primary key, index, check, and unique constraint, respectively.

          * the string name of a user-defined "token" that can be used
            to define new naming tokens.

          The values associated with each "constraint class" or "constraint
          mnemonic" key are string naming templates, such as
          ``"uq_%(table_name)s_%(column_0_name)s"``,
          which describe how the name should be composed.  The values
          associated with user-defined "token" keys should be callables of the
          form ``fn(constraint, table)``, which accepts the constraint/index
          object and :class:`_schema.Table` as arguments, returning a string
          result.