Method compile

lib/sqlalchemy/sql/elements.py:250–311

Compile this SQL expression. The return value is a :class:`~.Compiled` object. Calling ``str()`` or ``unicode()`` on the returned value will yield a string representation of the result. The :class:`~.Compiled` object also can return a dictionary of bind param

(
        self,
        bind: Optional[_HasDialect] = None,
        dialect: Optional[Dialect] = None,
        **kw: Any,
    )

    @util.preload_module("sqlalchemy.engine.default")
    @util.preload_module("sqlalchemy.engine.url")
    def compile(
        self,
        bind: Optional[_HasDialect] = None,
        dialect: Optional[Dialect] = None,
        **kw: Any,
    ) -> Compiled:
        """Compile this SQL expression.

        The return value is a :class:`~.Compiled` object.
        Calling ``str()`` or ``unicode()`` on the returned value will yield a
        string representation of the result. The
        :class:`~.Compiled` object also can return a
        dictionary of bind parameter names and values
        using the ``params`` accessor.

        :param bind: An :class:`.Connection` or :class:`.Engine` which
           can provide a :class:`.Dialect` in order to generate a
           :class:`.Compiled` object.  If the ``bind`` and
           ``dialect`` parameters are both omitted, a default SQL compiler
           is used.

        :param column_keys: Used for INSERT and UPDATE statements, a list of
            column names which should be present in the VALUES clause of the
            compiled statement. If ``None``, all columns from the target table
            object are rendered.

        :param dialect: A :class:`.Dialect` instance which can generate
            a :class:`.Compiled` object.  This argument takes precedence over
            the ``bind`` argument.

        :param compile_kwargs: optional dictionary of additional parameters
            that will be passed through to the compiler within all "visit"
            methods.  This allows any custom flag to be passed through to
            a custom compilation construct, for example.  It is also used
            for the case of passing the ``literal_binds`` flag through::

                from sqlalchemy.sql import table, column, select

                t = table("t", column("x"))

                s = select(t).where(t.c.x == 5)

                print(s.compile(compile_kwargs={"literal_binds": True}))

        .. seealso::

            :ref:`faq_sql_expression_string`

        """

        if dialect is None:
            if bind:
                dialect = bind.dialect
            elif self.stringify_dialect == "default":
                dialect = self._default_dialect()
            else:
                url = util.preloaded.engine_url
                dialect = url.URL.create(