Question

我尝试使用ActiveRecord构建查询，并且我发现在order（）之后执行limit（）和/或where（）不起作用。

这是我的代码：

candidates = Candidate.order("created_at desc")
puts candidates.to_sql
#prints SELECT "candidates".* FROM "candidates"   ORDER BY created_at desc
candidates.limit(20)
puts candidates.to_sql
#prints SELECT "candidates".* FROM "candidates"   ORDER BY created_at desc
candidates.where("first_name = ?", "Josh")
puts candidates.to_sql
#prints SELECT "candidates".* FROM "candidates"   ORDER BY created_at desc

我使用rails和activerecord（4.1.1）

Answer 1

我相信它的工作正如您所期望的那样，但结果是一个新的范围，而不是调整现有范围。即尝试这样的事情：

candidates = Candidate.order("created_at desc")
puts candidates.to_sql
#prints SELECT "candidates".* FROM "candidates"   ORDER BY created_at desc
candidates = candidates.limit(20)
puts candidates.to_sql

Answer 2

尝试将它们链接起来：

candidates = Candidate.where("first_name = ?", "Josh").limit(20).order("created_at desc")

订单后rails railsrecord limit

2 个答案: