Class ClauseAdapter

lib/sqlalchemy/sql/util.py:1047–1224

Clones and modifies clauses based on column correspondence. E.g.:: table1 = Table( "sometable", metadata, Column("col1", Integer), Column("col2", Integer), ) table2 = Table( "someothertable", metadata, Colu

class ClauseAdapter(visitors.ReplacingExternalTraversal):
    """Clones and modifies clauses based on column correspondence.

    E.g.::

      table1 = Table(
          "sometable",
          metadata,
          Column("col1", Integer),
          Column("col2", Integer),
      )
      table2 = Table(
          "someothertable",
          metadata,
          Column("col1", Integer),
          Column("col2", Integer),
      )

      condition = table1.c.col1 == table2.c.col1

    make an alias of table1::

      s = table1.alias("foo")

    calling ``ClauseAdapter(s).traverse(condition)`` converts
    condition to read::

      s.c.col1 == table2.c.col1

    """

    __slots__ = (
        "__traverse_options__",
        "selectable",
        "include_fn",
        "exclude_fn",
        "equivalents",
        "adapt_on_names",
        "adapt_from_selectables",
    )

    def __init__(
        self,
        selectable: Selectable,
        equivalents: Optional[_EquivalentColumnMap] = None,
        include_fn: Optional[Callable[[ClauseElement], bool]] = None,
        exclude_fn: Optional[Callable[[ClauseElement], bool]] = None,
        adapt_on_names: bool = False,
        anonymize_labels: bool = False,
        adapt_from_selectables: Optional[AbstractSet[FromClause]] = None,
    ):
        self.__traverse_options__ = {
            "stop_on": [selectable],
            "anonymize_labels": anonymize_labels,
        }
        self.selectable = selectable
        self.include_fn = include_fn
        self.exclude_fn = exclude_fn