Postgresql 查询中的Heroku dataclip变量替换

我想在查询的顶部设置一些参数/变量，并在Heroku Dataclips的复杂查询中的多个位置使用它们。 下面是一个简单的例子：

WITH vars AS ( SELECT 
  '2018-01-07' AS calcdate,
  12345 AS salary
)
select * 
from taxes
where country_alpha3='USA' and year='2018' and active=true 
and subdivision_code='US-MEDI' 
and local_code is null
and start_date <= DATE(vars.calcdate) and end_date >= DATE(vars.calcdate) 
and lower_amount_cents <= vars.salary and upper_amount_cents >= vars.salary;

我在2013年的另一个答案中看到了这种风格的代码，但到今天为止，它在实际的数据剪辑中还不起作用

Error: Your query couldn't be updated.

ERROR:  missing FROM-clause entry for table "vars" 
LINE 12: and start_date <=  DATE(vars.calcdate) and end_date >= DATE(v...
                                 ^

---

如果将vars.calcdate和vars.salary更改为常量，则SQL可以正常工作。这和vars有关。语法或用法，我想。

我找到了解决方案。就像我想象的那样。vars.name的格式是不允许的，我不确定在哪里看到的

WITH vars AS ( SELECT
  DATE('2018-01-07') AS calcdate,
  12345 AS salary
)
select *
from taxes
where country_alpha3='USA' and year='2018' and active=true
and subdivision_code='US-MEDI'
and local_code is null
and start_date <= (SELECT calcdate from vars) and end_date >= (SELECT calcdate from vars)
and lower_amount_cents <= (SELECT salary from vars) and upper_amount_cents >= (SELECT salary from vars);

---

为什么不呢？女巫错误？这是posgres允许cte的标准sql。使用错误消息和精确sql进行编辑