rails/rails — pull request #9220 by robertomiranda (2013-02-08 06:08:14+00:00)
Title: Change behaviour with empty hash in where clause

Raise ArgumentError instead of generate invalid SQL when empty hash is used in where clause value

For Example:

```ruby
Post.where(id: {})
=> SELECT "posts".* FROM "posts" WHERE (1 = 2)
```