Query on Params - ruby-on-rails

Question

I want to get records based on params received. Sometimes I receive 2 params or sometimes 3. I have written a code to get results when all 3 params received but when I receive only 1 param am getting 0 results.
Example
Office.where(state: params[:state], type: params[:type]).where("name like ?","%#{params[:name]}%")
When i get values like
{state: "KA", type: "private", name: "google"}
But when I get the only {name: "google"} I get no records
I have tried with condition
If params[:name].present? && params[:state].present? && params[:type].present?
query
elsif condition
query
end
Let me know how can I solve this or any better way

Answer 1

You can do something like this
In controller
filter_params = params.slice(:state, :type, :name)
Office.filter(filter_params)
In Office model
scope :state, -> (state) { where(state: state) }
scope :type, -> (type) { where(type: type) }
scope :name, -> (name) { where("name LIKE ?", "%#{name}%") }
def self.filter(filter_params)
results = where(nil)
filter_params.each do |key, value|
results = results.public_send(key, value) if value.present?
end
results
end
PS: It runs a single query irrespective of the number of params!
Hope that helps!

Answer 2

If a parameter is missing, it will probably be blank. If you pass them all in this will result in clauses like type = ''. For example, if only name is passed in you'll get something like...
where name like '%google%' and type = '' and state = ''
You need to strip out the blank fields. There are various ways to do this. Since you have a special case, the name clause, one good way to handle this is to build the query piece by piece.
query = Office.all
query = query.where(state: params[:state]) if params[:state].present?
query = query.where(type: params[:type]) if params[:type].present?
query = query.where("name like ?","%#{params[:name]}%") if params[:name].present?
The query does not execute until you fetch the values from query.
If there's a lot of simple parameters you can make a Hash and remove the pairs with a blank value.
qparams = {
state: params[:state],
type: params[:type]
}.select { |k,v|
v.present?
}
query = Office.where(qparams)
query = query.where("name like ?","%#{params[:name]}%") if params[:name].present?
Or use the handy compact_blank gem.
using CompactBlank
qparams = {
state: params[:state],
type: params[:type]
}.compact_blank
query = Office.where(qparams)
query = query.where("name like ?","%#{params[:name]}%") if params[:name].present?