Is there a way to transform the array of objects shown below:
[{ category:"AAA" },{ category:"BBB" },{ category: "CCC" }]
Into a new format like this:
["AAA","BBB","CCC"] , without relying on filtering or traditional array functions in the backend, but by utilizing MongoDB directly?
db.collection.distinct('category')This code snippet will return an array containing only unique values for the specified field.
The $map function is used to map the object keys within an array to a new array containing the corresponding key values. Following this, the output is transformed using the $addFields method.
arr = [{ category:"AAA" },{ category:"BBB" },{ category: "CCC" }];
db.collection.aggregate([
{
"$addFields": {
"exclude": {
"$map": {
"input": "$arr",
"as": "el",
"in": "$$el.category"
}
}
}
}
])
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