A reproducible bug script demonstrating that WHERE IIF doesn't behave as expected.

sqlite-where-iif-test.rb

# frozen_string_literal: true

require "bundler/inline"

gemfile(true) do
  source "https://rubygems.org"

  git_source(:github) { |repo| "https://github.com/#{repo}.git" }

  gem "sqlite3"
end

require "sqlite3"

$db = SQLite3::Database.new(":memory:")
$db.execute <<-SQL
  CREATE TABLE queues(
    name TEXT,
    value TEXT
  );
SQL

class WhereIIFTest < Minitest::Test
  def test_where_iif
    $db.execute("INSERT INTO queues(name, value) VALUES (?, ?), (?, ?)", ['default', 1], ['urgent', 10])
    
    where_iif = "SELECT COUNT(*) FROM queues WHERE iif(?, name = ?, 1)"
    
    assert_equal 2, $db.get_first_value(where_iif, nil)
    assert_equal 1, $db.get_first_value(where_iif, 'default')
    assert_equal 1, $db.get_first_value(where_iif, 'urgent')
  end
end