Today I Learned Ruby's Uniq Method Has Superpowers Using Ruby's Uniq Method with Multiple Conditions Cleaned Up a Dataset

I kinda always took the .uniq method for granted with just appending it to an Array.uniq.count type of usage. Not any more.

I have a project I’m working on that uses zipcodes to link a lot of data together. I have been looking at a way to reduce my table size from a 35K+ row count to a possible 3K row count by consolidating my data into unique values and passing the zipcodes into an array to optimize this dataset. I usually take the .uniq for granted when I’m using it to debug something. Once I took a closer look at the flexibility it has, I found it helpful in my use case.

Original Dataset
  => #<County2Zipcode:0x0000560360f9b758
  id: 1,
  state_fips: "1",
  state: "Alabama",
  state_abbr: "AL",
  zipcode: "35004",
  county: "St. Clair",
  city: "Acmar"

Transformed Dataset
  => #<CountyWithZipcode:0x0000560360124d50
  id: 3937,
  state: "Alabama",
  state_abbr: "AL",
  county: "St. Clair",
  zipcodes: ["35004", "35052", "35054", "35112", "35120", "35125", "35128", "35131", "35135", "35146", "35953", "35987"]>

RubyGuides had a cool post about the uniq method’s multiple condition functionality. This would allow me to pass the conditions in a block and transform the unique data in a way to create consolidated records. I was able to extract unique rows to build the new base CountyWithZipcode model, then conduct a second pass to pull all the zipcodes into an array. Here’s an example of the usage I found super helpful.

  # Create Uniq Records from County2Zipcode
  County2Zipcode.all.uniq {|record| [record.state, record.state_abbr, record.county]}.each do |new_record|
    valid_keys = ["state", "state_abbr", "county"]
    attrs = new_record.dup.slice(*valid_keys)