ruby on rails 3 - simple search within an array -

i want able search within micropost model. microposts have artist , song attributes. tagging these microposts use acts_as_taggable gem.

micropost model:

def self.search(search)   arel = order('created_at')   arel = arel.where('upper(artist) upper(?) or upper(song) upper(?)', "%#{search}%", "%#{search}%").order('created_at') if search.present?   arel end 

this code allows me search artist , song how can search tags?

micropost.find(1).tags returns [#actsastaggableon::tag id: 18, name: "rock", #actsastaggableon::tag id: 3, name: "rap"]

micropost.find(1).tags.map(&:name) returns array ["rock", "rap"]

how can query micropost's tags isn't in it's table artist , song? thank you.

something adding where() like?

where(self.tags.map(&:name), 'like upper(?)', "%#{search}%") 

can include link gem you're using? there few out there. 1 has built in: https://github.com/mbleigh/acts-as-taggable-on

speaking more generally, tags best implemented separate table joined objects opposed stored objects themselves. way can join tags table find objects.

more specifically, example near end looks backwards. have:

where(self.tags.map(&:name), 'like upper(?)', "%#{search}%") 

but (imho) should trying start tag , map object. like:

tag.where('like upper(?)', "%#{search}%").microposts