I have mongo query which does the group operation on the documents.
I have almost got the expected results except that I want to refine the results without empty or null values.
Currently my query looks like this:
db.productMetadata.aggregate([{$group:{"_id":{"color":"$productAttribute.colour","gender":"$productAttribute.gender"},"count" : {$sum : 1}}}]);
And the results looks something like this:
{ "_id" : { "color" : "BLUE", "gender" : "MEN" }, "count" : 1 }
{ "_id" : { }, "count" : 4 }
{ "_id" : { "color" : "NA", "gender" : "WOMEN" }, "count" : 1 }
{ "_id" : { "color" : "BLACK", "gender" : "MEN" }, "count" : 1 }
{ "_id" : { "color" : "BROWN", "gender" : "WOMEN" }, "count" : 1 }
{ "_id" : { "gender" : "MEN" }, "count" : 2 }
{ "_id" : { "color" : "BEIGE", "gender" : "MEN" }, "count" : 1 }
{ "_id" : { "color" : "BROWN", "gender" : "MEN" }, "count" : 1 }
I want to remove the rows if any of the group by field values are empty or null in the actual data of DB.
Excepted results should look something like this:
{ "_id" : { "color" : "BLUE", "gender" : "MEN" }, "count" : 1 }
{ "_id" : { "color" : "NA", "gender" : "WOMEN" }, "count" : 1 }
{ "_id" : { "color" : "BLACK", "gender" : "MEN" }, "count" : 1 }
{ "_id" : { "color" : "BROWN", "gender" : "WOMEN" }, "count" : 1 }
{ "_id" : { "color" : "BEIGE", "gender" : "MEN" }, "count" : 1 }
{ "_id" : { "color" : "BROWN", "gender" : "MEN" }, "count" : 1 }
You need an extra $match
pipeline step that will filter the incoming documents based on the embedded field "$productAttribute.colour"
existing and not null:
db.productMetadata.aggregate([
{
"$match": {
"productAttribute.colour": {
"$exists": true,
"$ne": null
}
}
},
{
"$group": {
"_id": {
"color": "$productAttribute.colour",
"gender": "$productAttribute.gender"
},
"count": {
"$sum": 1
}
}
}
]);