使用NOT与Squeel

Question

说我有一套条件:

Person.where{(name =~ 'Ernie%') & (salary < 50000) | (name =~ 'Joe%') & (salary > 100000)}

...将生成如下SQL:

SELECT "people".* FROM people
  WHERE ("people"."name" LIKE 'Ernie%' AND "people"."salary" < 50000)
  OR  ("people"."name" LIKE 'Joe%' AND "people"."salary" > 100000)

如何反转返回的集合,即更新Squeel以返回以下sql:

SELECT "people".* FROM people
  WHERE NOT(("people"."name" LIKE 'Ernie%' AND "people"."salary" < 50000)
  OR  ("people"."name" LIKE 'Joe%' AND "people"."salary" > 100000))

这有点人为,因为我的问题还涉及一组动态生成的条件 - 我无法改变实际条件,只需要将它们包装在NOT()中.

任何关于在哪里寻找的想法或建议？

Answer 1

你会想要使用一元减号运算符.

Person.where{-((name =~ 'Ernie%') & (salary < 50000) | (name =~ 'Joe%') & (salary > 100000))}.to_sql
=> "SELECT \"people\".* FROM \"people\"  WHERE (NOT (((\"people\".\"name\" LIKE 'Ernie%' AND \"people\".\"salary\" < 50000) OR (\"people\".\"name\" LIKE 'Joe%' AND \"people\".\"salary\" > 100000))))"