appending conditions in a model

I have a Search Model which contains search data. It looks like this:

keywords:string by_user:boolean by_title:boolean ...

So basically what I want is, if one of the booleans is true it will search that particular index. So if by_user is true and by_title is true, it will search the database of stories by user and title. If only by_user is true, then it will only search by user.

So here's what I'm planning in the Search Model:

def stories find_stories end

def find_stories find(:all, :conditions => ??) end

I'm confused has to how to make the conditions since it will have to check which booleans are true and then append onto the conditions. How would I do this?

I have a Search Model which contains search data. It looks like this:

keywords:string by_user:boolean by_title:boolean

[...]

def find_stories find(:all, :conditions => ??) end

I'm confused has to how to make the conditions since it will have to check which booleans are true and then append onto the conditions. How would I do this?

Remember, :conditions can take a hash, which means you can do what you want if you get your head out of ActiveRecord for a minute and into Ruby hash-munging. :slight_smile: So for example:

def find_stories(by_user = false, by_title = false)   conditions = {}   conditions[:user] = 'some criteria' if by_user   conditions[:title] = 'more criteria' if by_title   Story.find(:all, :conditions => conditions.merge(:any => 'other', :options => 'you want') end

Does that help?

Best,

Yeah, that helps a lot. I actually realized that a little bit after posting and looked it up on Google, but this confirms it. Thanks!

You can also use the :symbol interpolation support in conditions, to get code that looks like this:

def self.find_stories # add parameters as needed   conditions = ['1 = 1'] # default; find complains if conditions is empty   conditions << 'title LIKE :search' if by_title   conditions << 'user LIKE :search' if by_user   Story.find(:all, :conditions => [conditions.join(' AND '), {:search => "%#{keywords}%"}]) end

This simple example works for a single search term; extending it to split keywords on spaces and combine terms with ' OR ' (or ' AND ', depending on your interpretation of keywords) is fairly straightforward.

If you're doing more complicated things in your searches, you might also want to try using named scopes instead. Something like:

def self.find_stories   proxy = Story   proxy = proxy.search_by_title(keywords) if by_title   proxy = proxy.search_by_user(keywords) if by_user   proxy end

...where the scopes are defined on Story thus:

class Story < AR::Base   named_scope :search_by_title, lambda { |keywords| kws = keywords.split(/ /); { :conditions => [kws.map { |k| 'title LIKE ?' }.join(' AND '), *(kws.map { |k| "%#{k}%" })] } }

end

and so on for user, where you can now add options like :joins and/ or :include if user is defined on another table.

--Matt Jones

Wow, thanks for that! I'm using thinking sphinx, but the same thing applies, right?