I have the following doc scheme:
{
"_id": 123123123,
"linhas": [1,2,3]
}
And i want all of them to turn to the following scheme:
{
"_id": 123123123,
"linhas": [{
"id":1,
"duracao": 14
},{
"id":2,
"duracao": 14
},{
"id":3,
"duracao": 14
}]
}
I other words, i want all numbers from the array to turn into ids of objects inside the same array. How can i do that with a mongo query?
You can use the .aggregate() method like this:
db.collection.aggregate([
{ "$unwind": "$linhas" },
{ "$group": {
"_id": "$_id",
"linhas": {
"$push": {
"id": "$linhas",
"duracao": { "$literal": 14 }
}
}
}}
])
Which returns:
{
"_id" : 123123123,
"linhas" : [
{
"id" : 1,
"duracao" : 14
},
{
"id" : 2,
"duracao" : 14
},
{
"id" : 3,
"duracao" : 14
}
]
}
You need to deconstruct your "linhas" array using the $unwind operator then $group your documents by "_id" and use the $push accumulator operator to return array of subdocuments. Of course the $literal operator let you set the value for the new field "duracao".
