s0TQMR7d

1ActiveRecord::Base.connection.execute('DROP TABLE IF EXISTS non_duplicate_cat_typles')
2
3ActiveRecord::Base.connection.execute(<<-SQL)
4  CREATE TABLE non_duplicate_cat_typles (
5    id serial primary key,
6    main_id integer NOT NULL,
7    non_duplicate_id integer NOT NULL
8  );
9SQL
10
11class NonDuplicateTyples < ActiveRecord::Base
12end
13
14class NonDuplicates
15  # include SqlImplementation
16  # include RubyImplementation
17  def non_duplicates
18    raise 'Implement me!'
19  end
20
21  def include?(*typle)
22    raise 'Implement me!'
23  end
24end
25
26not_duplicates = NonDuplicates.new
27cat_duplicates = []
28# We have a place where 
291.upto(100_000).each do |remote_cat_id|
30  1.upto(100_000).each do |cat_id|
31    next if not_duplicates.include?(cat_id, remote_cat_id)
32    # we need to check if the 
33    cat_duplicates << [remote_cat_id, cat_id]
34  end
35end
36
37# We were wondering about two implementations of NonDuplicates and we call them with
38# naive names SqlImplementation and RubyImplementation
39
40module SqlImplementation
41  def not_duplicates
42    return @not_duplicates if @not_duplicates
43    
44    result =
45      connection.execute <<-SQL
46        WITH all_non_duplicates AS (
47          SELECT main_id AS main, non_duplicate_id AS non_duplicate
48          FROM non_duplicate_cat_typles
49          
50          UNION
51          
52          SELECT non_duplicate_id AS main, main_id AS non_duplicate
53          FROM non_duplicate_cat_typles
54        )
55        SELECT main, array_agg(non_duplicate) FROM all_non_duplicates GROUP BY main;
56      SQL
57
58    @not_duplicates =
59      result.
60        values.
61        to_h.
62        transform_values { |v| PG::TextDecoder::Array.new.decode(v).map(&:to_i) }
63  end
64
65  def include?(first_id, second_id)
66    @not_duplicates[first_id]&.include?(second_id)
67  end
68end
69
70module RubyImplementation
71  def not_duplicates
72    @not_duplicates =
73      NonDuplicateTyples.
74        pluck(:main_id, :non_duplicate_id).
75        map(&:to_set).
76        to_set
77  end
78end