Multiple sums with different calculations mongodb - mongodb

Question

maybe someone can help me. I have the following table in mongodb and I need to perform the following calculation:
Odds:
High
Average
Low
For each probability, a multiplier must be applied
Example:
High probability: Value * 0.87
Average probability: Value * 0.5
Low Probability: Value * 0.06
I made the following query in the db mongo, but I can apply only one multiplier. I was unable to differentiate each probability to multiply by the above values.
db.teste.aggregate(
{
$match: {
$and: [
{
"converted_fields.Probabilidade de fechamento": {
$ne: null
},
"current.value": {
$ne: 0
},
"current.add_time": {
$gte: ISODate("2020-07-01")
},
}
]
}
},
{
$project: {
"_id": "$_id",
"___group": {
"probabilidade": "$converted_fields.Probabilidade de fechamento"
},
"current___value": "$current.value"
}
},
{
$group: {
"_id": "$___group",
"count": {
$sum: "$current___value"
}
}
},
{
$project: {
"_id": 0,
"probabilidade": "$_id.probabilidade",
"valor": {
$multiply: ["$count", 0.5]
}
}
}
)
Result:
{
Alta - 379,5
Média - 1647,9
Baixa - 3763,32
}
how do I separate a different multiplier for each probability?

Answer 1

The aggregation might look something like this:
db.teste.aggregate([
{
$match: {
$and: [
{
"converted_fields.Probabilidade de fechamento": {
$ne: null
},
"current.value": {
$ne: 0
},
"current.add_time": {
$gte: ISODate("2020-07-01")
},
}
]
}
},
{
$group: {
_id: "$converted_fields.Probabilidade de fechamento",
count: { $sum: "$current.value"}
}
},
{
$project:
{
_id: 1,
valor:
{
$switch:
{
branches: [
{
case: { $eq: [ "$_id", "Alta"] },
then: { $multiply: ["$count", 0.87] }
},
{
case: { $eq: [ "$_id", "Médica"] },
then: { $multiply: ["$count", 0.5] }
},
{
case: { $eq: [ "$_id", "Baixa"] },
then: { $multiply: ["$count", 0.06] }
}
],
default: 0
}
}
}
},
{
$group: {
_id: null,
probabilidades: {
$push: {
k: "$_id",
v: "$valor"
}
}
}
},
{
$replaceRoot: {
newRoot: {
$arrayToObject: "$probabilidades"
}
}
}
])
The first $match stage is still as you had it. In my solution the first $group stage will return documents of this form:
{
_id: 'Alta',
count: 100
}
In the following $project stage, I use the $switch operator in order to determine what to multiply count by in order to get the correct valor. Using the sample document I showed before, this stage will return documents that look like this:
{
_id: 'Alta',
valor: 87
}
Next is another $group stage, where I group all of the probability documents together, and push them into an array. The document from this stage might look like this:
{
_id: null,
probabilidades: [
{ 'k': 'Alta', 'v': 87 },
{ 'k': 'Baixa', 'v': 6 }
]
}
In the final stage, $replaceRoot, I use $arrayToObject to turn the probabilidades array into your desired output.