Class Column

lib/sqlalchemy/sql/schema.py:1497–2702

Represents a column in a database table.

class Column(DialectKWArgs, SchemaItem, ColumnClause[_T]):
    """Represents a column in a database table."""

    __visit_name__ = "column"

    inherit_cache = True
    key: str

    server_default: Optional[FetchedValue]

    def __init__(
        self,
        __name_pos: Optional[
            Union[str, _TypeEngineArgument[_T], SchemaEventTarget]
        ] = None,
        __type_pos: Optional[
            Union[_TypeEngineArgument[_T], SchemaEventTarget]
        ] = None,
        *args: SchemaEventTarget,
        name: Optional[str] = None,
        type_: Optional[_TypeEngineArgument[_T]] = None,
        autoincrement: _AutoIncrementType = "auto",
        default: Optional[Any] = _NoArg.NO_ARG,
        insert_default: Optional[Any] = _NoArg.NO_ARG,
        doc: Optional[str] = None,
        key: Optional[str] = None,
        index: Optional[bool] = None,
        unique: Optional[bool] = None,
        info: Optional[_InfoType] = None,
        nullable: Optional[
            Union[bool, Literal[SchemaConst.NULL_UNSPECIFIED]]
        ] = SchemaConst.NULL_UNSPECIFIED,
        onupdate: Optional[Any] = None,
        primary_key: bool = False,
        server_default: Optional[_ServerDefaultArgument] = None,
        server_onupdate: Optional[_ServerOnUpdateArgument] = None,
        quote: Optional[bool] = None,
        system: bool = False,
        comment: Optional[str] = None,
        insert_sentinel: bool = False,
        _omit_from_statements: bool = False,
        _proxies: Optional[Any] = None,
        **dialect_kwargs: Any,
    ):
        r"""
        Construct a new ``Column`` object.

        :param name: The name of this column as represented in the database.
          This argument may be the first positional argument, or specified
          via keyword.

          Names which contain no upper case characters
          will be treated as case insensitive names, and will not be quoted
          unless they are a reserved word.  Names with any number of upper
          case characters will be quoted and sent exactly.  Note that this
          behavior applies even for databases which standardize upper
          case names as case insensitive such as Oracle Database.