ActiveRecord:如何查找布尔字段不为真的记录？

Question

我如何组合下面的两个查询？

    1.9.3-p484 :003 > u = User.where(guest: false).count
       (2.4ms)  SELECT COUNT(*) FROM `users` WHERE `users`.`guest` = 0
     => 0 
    1.9.3-p484 :004 > u = User.where(guest: nil).count
       (2.5ms)  SELECT COUNT(*) FROM `users` WHERE `users`.`guest` IS NULL
     => 4150

我想抓住guest列中具有nil或false值的用户(在一个语句中).

Answer 1

User.where(guest: [false, nil]).count

这将生成如下查询:

SELECT COUNT(*) FROM "users" WHERE (("users"."guest" = 'f' OR "users"."guest" IS NULL))

要么

User.where.not(guest: true).count

这将生成如下查询:

SELECT COUNT(*) FROM "users" WHERE ("users"."guest" != 't')

第二个将比第一个花费更少的时间.