Slice only one element from an array in MongoDB
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Let’s say we have two documents in a MongoDB collection called scores and I would like to fetch the latest score of Ron. I need to fetch the latest element from an array of scores and we can use $slice for this purpose.
[
{
"_id": {
"$oid": "5e16e8a3c3775d62f3acbe6e"
},
"name": "Naveen",
"score": [
9,
8,
18,
76,
65,
4,
0,
8
]
},
{
"_id": {
"$oid": "5e16e8a3c3775d62f3acbe71"
},
"name": "Ron",
"score": [
19,
82,
8,
6,
45,
45,
99,
8
]
}
]To fetch the latest score of Ron, we can query the collection like this.
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db.scores.findOne({name: "Ron"},{score : {$slice : 1} ,"name":0,"_id":0}){"score":[19]}
