Docs for DAL.executesql.im_func

        Executes an arbitrary query

        Args:
            query (str): the query to submit to the backend
            placeholders: is optional and will always be None.
                If using raw SQL with placeholders, placeholders may be
                a sequence of values to be substituted in
                or, (if supported by the DB driver), a dictionary with keys
                matching named placeholders in your SQL.
            as_dict: will always be None when using DAL.
                If using raw SQL can be set to True and the results cursor
                returned by the DB driver will be converted to a sequence of
                dictionaries keyed with the db field names. Results returned
                with as_dict=True are the same as those returned when applying
                .to_list() to a DAL query.  If "as_ordered_dict"=True the
                behaviour is the same as when "as_dict"=True with the keys
                (field names) guaranteed to be in the same order as returned
                by the select name executed on the database.
            fields: list of DAL Fields that match the fields returned from the
                DB. The Field objects should be part of one or more Table
                objects defined on the DAL object. The "fields" list can include
                one or more DAL Table objects in addition to or instead of
                including Field objects, or it can be just a single table
                (not in a list). In that case, the Field objects will be
                extracted from the table(s).

                Note:
                    if either `fields` or `colnames` is provided, the results
                    will be converted to a DAL `Rows` object using the
                    `db._adapter.parse()` method
            colnames: list of field names in tablename.fieldname format

        Note:
            It is also possible to specify both "fields" and the associated
            "colnames". In that case, "fields" can also include DAL Expression
            objects in addition to Field objects. For Field objects in "fields",
            the associated "colnames" must still be in tablename.fieldname
            format. For Expression objects in "fields", the associated
            "colnames" can be any arbitrary labels.

        DAL Table objects referred to by "fields" or "colnames" can be dummy
        tables and do not have to represent any real tables in the database.
        Also, note that the "fields" and "colnames" must be in the
        same order as the fields in the results cursor returned from the DB.