I have a collection that looks like this
{
balance: string
symbol: string
address: string
}
I want to query that collection using an aggregation as following:
input array addresses[]
query collection where collection.address contained in provided address Array and SUM all balances grouped by symbol.
The desired output should look like this:
[
{symbol: xy, balance: summedBalanceForThisSymbol},
{symbol: yz, balance: summedBalanceForThisSymbol},
]
I am rather new to mongoDB, this is what I have which doesnt work at all.
const pipe = [
{
match: [
{
address: { $in: addresses } //addresses is an array of string values
}
]
},
{
group: {
objectId: "$symbol",
balance: { $sum: "$balance" }
}
}
]
I have to use objectId instead of _id because the SDK I am using requires to do so. I also need the string balance values to be converted to a number (I guess double) before summing up.
You are very close, you just have some minor syntax errors, this is how you should do it:
(One thing to mentioned is this requires balance to be a valid number string, if not the pipeline will throw an error)
db.collection.aggregate([
{
$match: {
address: {
$in: addresses
}
}
},
{
$group: {
_id: "$symbol",
sum: {
$sum: {
"$toInt": "$balance"
}
}
}
}
])