# Ejemplo $group

## $group: (Contar los documentos agrupados por activo)

* Contar los artículos  agrupados por $activo

| Orden                                                                                            | Salida                                                                                                                                  |
| ------------------------------------------------------------------------------------------------ | --------------------------------------------------------------------------------------------------------------------------------------- |
| db.articulo.aggregate(\[ {"$group": {"\_id": {"\_activo" : "$activo"}, "total": {"$sum": 1}}} ]) | { "\_id" : { "\_activo" : "si" }, "total" : 1790 }                                      { "\_id" : { "\_activo" : "no" }, "total" : 2 } |

* **aggregateFromDocument()/Cuenta el numero de documentos agrupado por activo**
* Lo agrupamos por activo
* Contar los documentos y colocarlos en la variable cantidad

```java
List<Document> documentList = Arrays.asList(

              new Document("$group",
              new Document("_id", "$" + "activo").append("cantidad", new Document("$sum", 1))));

List<JmoordbResult> list = articuloRepository.aggregateFromDocument(documentList);

            if (list == null || list.isEmpty()) {
                System.out.println("No hay articulos con esa condicion");
            } else {

                list.forEach((a) -> {
                    System.out.println("_id " + a.get("_id") + " Cantidad: " + a.get("cantidad"));
                });

            }
```

## ![](/files/-Lc1WvbbXDuvqq7oihcQ)

*


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