I have 2 hstore columns (parameters and keys) defined in my PostgeSQL database. I want to get a list of keys and have defined a method for it in the model:
def self.keys_list
logs = self
list = Log.column_names - %w{id parameters extras}
logs.each do |log|
log.parameters.present? ? list << log.parameters.keys : list << []
log.extras.present? ? list << log.extras.keys : list << []
end
list = list.flatten.uniq
return list
end
But when I try using it, I get the following error:
NoMethodError: undefined method `each' for #<Class:0x00000004b630b0>
Can anyone suggest where the error is or how to do it some other way?
ActiveRecord::Base does not define an .each method. You need to add in a call to all, like so:
all.each do |log|
#...
end
This should make both Log.keys_list and Log.where(name: "Peeyush").keys_list work.
Related
I have the following code:
wedding = Wedding.where(location_id: user_params[:locationId])
wedding.map(&:guests).each do |member|
user_ids << member.ids
end
In my case :guests is a active record table, but I have a couple that I would like to pass thru map to generate the user_ids
So it would be array of methods like this, that I would like to pass: [guests, bride, etc etc]
It would be even better if I could pass the whole array, but otherwise if I can step through the array of methods that would be great too.
Any ideas?
EDIT:
I'm trying this with no luck.. I get: NameError (wrong constant name guests):
roles = ["guests"]
wedding = Wedding.where(location_id: user_params[:locationId])
roles.each do |role|
clazz = Kernel.const_get(role)
wedding.map(&:clazz).each do |member|
user_ids << member.ids
end
end
Below, i pass an array of methods to members of the array weddings:
weddings = Wedding.where(location_id: user_params[:locationId])
# array with methods you're interested in
methods=[:guests, :bride]
# looping through the weddings array
weddings.each do |wedding|
# looping through the methods array
methods.each do |method|
# for each wedding, passing every method to the wedding
members=wedding.public_send(method)
members.each do |member|
# storing the values
user_ids << member.ids
end
end
end
Rails 5.2
I have a Catalog model, with the following methods:
def current_items
....
end
def sales_items
....
end
There are more than a dozen methods, and I would like to do, in my helper, is to define an array
categories = ['current', 'sales', ....]
categories.each do |category|
m = "{category}_items"
#items = Catalog.m
...
end
But, I am getting an error:
undefined method 'm' for Catalog:Class
Any idea if this can be done?
Please try below code :-
class Catalog < ActiveRecord::Base
def self.current_items
puts "from current_items"
end
def self.sales_items
puts "from sales_items"
end
end
Then call using :-
if public
m = "#{category}_items"
#items = Catalog.public_send(m)
if private
m = "#{category}_items"
#items = Catalog.send(m)
thanks :)
Try public_send to call the public methods in class, use send if you want to call private methods as well but avoid using send if not needed
m = "#{category}_items"
Catalog.public_send(m)
Give it a try!
I have multiple columns I need to pull unique values from and compile an array of each unique value. Using uniq.pluck(:column_name) works, but how do I iterate over an array of column names?
react = []
fields = [reactivity_1, reactivity_2, reactivity_3, reactivity_4]
fields.each do |field|
puts "Parsing #{field}"
Raw.all.uniq.pluck(field).each do |r|
unless react.include? r
puts "Adding #{r} to Array."
react << r
else
puts "#{r} Exists."
end
end
end
Error:
NameError: undefined local variable or method `reactivity_1' for main:Object
You will need to make the column names strings or symbols, like this Ruby thinks it is a local varaible or method.
react = Set.new
fields = [:reactivity_1, :reactivity_2, :reactivity_3, :reactivity_4]
fields.each do |field|
puts "Parsing #{field}"
Raw.all.uniq.pluck(field).each do |r|
react << r
end
end
If you want to make sure that a collection does not contain duplicate, you can use a Set:
require "set"
set = Set.new
set << "foo"
set << "bar"
set << "bar"
puts set.size #> 2
I've rewritten your code sample to use Set.
Can you describe what you are trying to achieve? Perhaps there is an easier way to get the data out of the DB.
I want to filter jobs on the parameter passed onto the model, currently search works flawlessly without query passed into the model, but when I type query it doesn't return anything. How can I perform this query with query and criteria.
results << model.with_query(query).where(criteria). any idea would be really appreciated.
module Refinery
class SearchEngine
# How many results should we show per page
RESULTS_LIMIT = 100
# Perform search over the specified models
def self.search(query, job_region, job_division, country, job_type, page = 1)
results = []
Refinery.searchable_models.each do |model|
criteria = {:job_region => job_region,
:job_division => job_division,
:country => country,
:job_type => job_type
}.select { |key, value| value.present? }
if query.present?
results << model.with_query(query).where(criteria)
else
results << model.limit(RESULTS_LIMIT).where(criteria)
end
end
results.flatten[0..(RESULTS_LIMIT - 1)]
end
end
end
The problem here is that the method .with_query(qry) returns an Array. You want to do chain-scoping, so you must use scopes that returns ActiveRecord::Relation objects.
model.with_query(query)
# returns an Array
model.with_query(query).where(criteria)
# calling .where on an Array object => NoMethodError
model.where(criteria)
# returns an ActiveRecord::Relation
model.where(criteria).with_query(query)
# calls the query on an AR::Relation object, which is doable
Short version: Change this:
results << model.with_query(query).where(criteria)
To this:
results << model.where(criteria).with_query(query)
I've written the following method to combine the References of Sections model and it's children:
def combined_references
ids = []
ids << self.id
self.children.each do |child|
ids << child.id
end
Reference.where("section_id = ?", ids)
end
But section.combined_references returns the following error:
Mysql2::Error: Operand should contain 1 column(s): SELECT `references`.* FROM `references` WHERE (section_id = 3,4)
It seems to have collected the correct values for ids, have I structured the query incorrectly?
Transform last line to:
Reference.where(section_id: ids)
and it should produce:
SELECT `references`.* FROM `references` WHERE section_id IN (3,4)
And you can shorten your code by one line with :
ids = []
ids << self.id
to
ids = [self.id]
it's invalid statement
WHERE (section_id = 3,4)
correct would be
WHERE (section_id in (3,4))
Please use:
Reference.where(:section_id => ids)
You can try something like this instead:
def combined_references
ids = self.children.map(&:id).push(self.id)
Reference.where(section_id: ids)
end
You can also query the database with:
Reference.where("section_id in (?)", ids)
The following has the most readability in my opinion:
def combined_references
Reference.where(section_id: self_and_children_ids)
end
private
def self_and_children_ids
self.children.map(&:id).push(self.id)
end