I have objects that have a min/max age range on them:
name: "Event 1"
type: Package # inheritance
min_age: 1
max_age: 8
category_id: 2 # Birthday
I would like to select and return these objects based on user preference of age and type by looking if the object's age range satisfies the inputted number.
Currently I am stuck with:
Controller code:
age = params[:age]
item_type = params[:item_type]
@all_items = Item.where("categories.name = ?", 'birthday')
@events = @all_items.where("(type: #{item_type}) AND ...here I need to lookup if the #{age} variable is within the object range")
Now the problem is that I need to pick a birthday event by inputted user number, having Range on the object itself. Is there a way of doing that without going through every single object?
@events = @all_items.where("type = #{item_type} AND min_age >= #{age} AND max_age <= #{age}")
I suppose the associations look as follows:
Item has_many :categories
Category belongs_to :item
In this case
Item.where("categories.name = ?", 'birthday')
will most likely fail because categories are not joined with something like
ActiveRecord::StatementInvalid: PG::UndefinedTable: ERROR: missing FROM-clause entry for table "categories"
Here is what you'll want to do:
Item.joins(:categories)
.where(categories: { name: 'birthday' })
.where("items.type = '#{item_type}' AND items.min_age >= #{age} AND items.max_age <= #{age}")
.group('items.id')
Using PostgreSQL's BETWEEN might make the query look nicer and shorter:
Item.joins(:categories)
.where(categories: { name: 'birthday' })
.where("items.type = '#{item_type}' AND #{age} BETWEEN items.min_age AND items.max_age")
.group('items.id')