Group and add json return data with jquery

Question

I have this Json that returns from the database, I need to consolidate the data that are equal but I have no idea how to do in jquery or php. If anyone has any suggestions!

  {  
   "data":[  
      {  
         "nome_pesquisa":"teste",
         "nr_pergunta":"1",
         "pergunta":"a",
         "qtd":"40"
      },
      {  
         "nome_pesquisa":"teste",
         "nr_pergunta":"2",
         "pergunta":"b",
         "qtd":"29"
      },
      {  
         "nome_pesquisa":"teste",
         "nr_pergunta":"2",
         "pergunta":"b",
         "qtd":"11"
      },
      {  
         "nome_pesquisa":"teste",
         "nr_pergunta":"3",
         "pergunta":"c",
         "qtd":"3"
      },
      {  
         "nome_pesquisa":"teste",
         "nr_pergunta":"3",
         "pergunta":"c",
         "qtd":"5"
      },
      {  
         "nome_pesquisa":"teste",
         "nr_pergunta":"3",
         "pergunta":"c",
         "qtd":"2"
      }
   ]
}

Answer 1

To reduce the array by leaving only one entry for each question, distinguishing through the nr_pergunta, can use the function reduce.

For each element look for if it exists, and if it already exists add the amount. When it does not exist just add it to the array being built.

Implementation:

let json = `
{
	"data": [{
			"nome_pesquisa": "teste",
			"nr_pergunta": "1",
			"pergunta": "a",
			"qtd": "40"
		},
		{
			"nome_pesquisa": "teste",
			"nr_pergunta": "2",
			"pergunta": "b",
			"qtd": "29"
		},
		{
			"nome_pesquisa": "teste",
			"nr_pergunta": "2",
			"pergunta": "b",
			"qtd": "11"
		},
		{
			"nome_pesquisa": "teste",
			"nr_pergunta": "3",
			"pergunta": "c",
			"qtd": "3"
		},
		{
			"nome_pesquisa": "teste",
			"nr_pergunta": "3",
			"pergunta": "c",
			"qtd": "5"
		},
		{
			"nome_pesquisa": "teste",
			"nr_pergunta": "3",
			"pergunta": "c",
			"qtd": "2"
		}
	]
}`;

let perguntas = JSON.parse(json).data;
//tornar a quantidade numérica para a soma funcionar como esperado
perguntas.forEach(perg => perg.qtd = Number(perg.qtd)); 

let perguntasAgrupadas = perguntas.reduce(function(acc, curr){
  let encontrado = false;
  for (let pergunta of acc){
    if (pergunta.nr_pergunta == curr.nr_pergunta){
      pergunta.qtd += curr.qtd;
      encontrado = true;
      break;
    }
  }
  
  if (!encontrado)
    acc.push(curr);
  
  return acc;
}, []);

console.log(perguntasAgrupadas);

Answer 2

You can also use filter after adding and deleting the repeated items (remembering that the method below is compatible with IE):

var json = {  
   "data":[  
      {  
         "nome_pesquisa":"teste",
         "nr_pergunta":"1",
         "pergunta":"a",
         "qtd":"40"
      },
      {  
         "nome_pesquisa":"teste",
         "nr_pergunta":"2",
         "pergunta":"b",
         "qtd":"29"
      },
      {  
         "nome_pesquisa":"teste",
         "nr_pergunta":"2",
         "pergunta":"b",
         "qtd":"11"
      },
      {  
         "nome_pesquisa":"teste",
         "nr_pergunta":"3",
         "pergunta":"c",
         "qtd":"3"
      },
      {  
         "nome_pesquisa":"teste",
         "nr_pergunta":"3",
         "pergunta":"c",
         "qtd":"5"
      },
      {  
         "nome_pesquisa":"teste",
         "nr_pergunta":"3",
         "pergunta":"c",
         "qtd":"2"
      }
   ]
}

var temp_array = [];

$.each(json.data, function(e,v){
   var items = v.nr_pergunta+v.pergunta;
   
   if(temp_array.indexOf(items) == -1){
      temp_array.push(e);
      temp_array.push(items);
   }else{
      var array_pos = temp_array[temp_array.indexOf(items)-1];
      var soma = parseInt(json.data[array_pos].qtd) + parseInt(v.qtd);
      json.data[array_pos].qtd = soma.toString();
      delete json.data[e];
   }
});

json = json.data.filter(function(n){ return n }); 

console.log(json);

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