This is my collection structure in MongoDB:
{
_id: id,
name: name,
loans: [
[{id: 1, acName: "ABC"}],
[{id: 2, acName: "DEF"}],
[{id: 3, acName: "GHI"}]
]
}
How can I update acName of a specific ID? Let's say, I want to update acName of id 2. How can I do that?
Solution 1: Without arrayFilters
Use $elemMatch to find the existence of id: 2 in nested arrays.
With all positional operator ($[]) to update the respective document field.
db.collection.update({
"loans": {
$elemMatch: {
$elemMatch: {
id: 2
}
}
}
},
{
$set: {
"loans.$.$[].acName": "<NEW VALUE>"
}
})
Demo Solution 1 @ MongoPlayground
Solution 2: With arrayFilters
Use $elemMatch to find the existence of id: 2 in nested arrays.
With filtered positional operator ($[<identifier>]) and arrayFilters to update the respective document field.
db.collection.update({
"loans": {
$elemMatch: {
$elemMatch: {
id: 2
}
}
}
},
{
$set: {
"loans.$.$[loan].acName": "<NEW VALUE>"
}
},
{
arrayFilters: [
{
"loan.id": 2
}
]
})
