如何在ActiveRecord中创建“OR”语句？

Question

I am trying to create an 'OR' sql statement in ActiveRecord 3, I tried all kinds of variations but can't figure it out...

For example I want this query to include multiple 'channel_ids' and have it return all posts for any of the channel IDs. This works for one:

Post.where(:user => 'mike').where(:channel_id => 0).limit(20)

but I cant figure out how to do it with multiples, I've tried for example:

Post.where(:user => 'mike').where(:channel_id => ?, [0,1,2,3]).limit(20) 

but it didn't work. How can I make this work?

Answer 1

试试这个：

Post.where("posts.user = ? OR posts.channel_id IN (?)", "mike", ids)

Answer 2

Use the Arel methods to do this:

t = Post.arel_table
ids = [1,2,3]

Post.where(
  t[:user].eq("mike").or(t[:channel_id].in(ids))
)