Number作为SQLAlchemy查询中的列

Question

如何在SQL查询中表达“c”列，如下所示：

SELECT a, b, 0 AS c
FROM mytable

SQLAlchemy代码：

session.query(mytable.c.a, mytable.c.b, {???, c is a dynamic column})

Answer 1

from sqlalchemy.sql.expression import literal_column
session.query(mytable.c.a, mytable.c.b, literal_column(u'0').label(u'c'))