How to populate all items in a dataset with aggregated (Sum) data from another dataset?

[J.D]

export function sumUp(vendorId){
return wixData.aggregate('Vendors')
.having(wixData.filter().eq('vendorId', vendorId))
.group('vendorId')
.sum('payments')
.run()
.then(res => {
    const items = res.items;
    let sum = 0;
    if(items.length > 0){
        sum = items[0].paymentsSum;
    }
    return sum;
})
}