{
  "fields": [{"id":"_id","type":"int"},{"id":"id","type":"int4"},{"id":"nombre","type":"text"}],
  "records": [
    [1,1,"Prehistoria"],
    [2,2,"Protohistoria"],
    [3,3,"Edad Antigua"],
    [4,4,"Edad Media"],
    [5,5,"Edad Moderna"],
    [6,6,"Edad Contemporánea"]
]}