exec_with_cursor.rb

def self.exec_with_cursor(sql, params: [], buffer_size: 10_000)
  raise ArgumentError, 'Must provide a block' unless block_given?

  cursor_name = "C#{SecureRandom.hex}"
  sql = "DECLARE #{cursor_name} CURSOR FOR #{sql}"

  connection.transaction do
    connection.exec_params(sql, params)
    loop do
      res = connection.exec("FETCH #{buffer_size} IN #{cursor_name}")
      break if res.ntuples <= 0
      
      yield res
    end
  end
end