I have three queries and now I want to change this to MongoDB aggregation and below is the code:
db.mycollection.count({$and:[$requestB:{$exists:false},[$requestC:{$exists:false}]})
db.mycollection.count({requestB:{$exists:true}})
db.mycollection.count({requestC:{$exists:true}})
Now i want to change this code to aggregation but it did not work
db.mycollection.aggregate( [
{ $group: {
'_id' : { user_id: '$user_id'},
requestA_count: { $sum: {
$cond: [ {$and: [{$eq: ["$requestB", null]}, {$eq: ["requestC", null]}}}, 1, 0 ]
} },
requestB_count: { $sum: {
$cond: [ {requestB:{'$exists':true}}, 1, 0 ]
} },
requestC_count: { $sum: {
$cond: [ {requestC:{'$exists':true}}, 1, 0 ]
} },
} },
{ $project: {
_id: 0,
user_id: '$_id.user_id',
requestA_count: 1,
requestB_count: 1,
requestC_count: 1
} }
] );
You can use $type
instead of $exists
inside $group
,
db.collection.aggregate([
{
$group: {
"_id": { user_id: "$user_id" },
requestA_count: {
$sum: {
$cond: [
{
$and: [
{ $ne: [{$type: "$requestA"}, "missing"] },
{ $eq: [{$type: "$requestB"}, "missing"] },
{ $eq: [{$type: "$requestC"}, "missing"] }
]
}, // you need to close bracket here not below
1, 0
]
}
},
requestB_count: {
$sum: { $cond: [{ $ne: [{ $type: "$requestB" }, "missing"] }, 1, 0] }
},
requestC_count: {
$sum: { $cond: [{ $ne: [ { $type: "$requestC" }, "missing" ] }, 1, 0] }
}
}
},
{
$project: {
_id: 0,
user_id: "$_id.user_id",
requestA_count: 1,
requestB_count: 1,
requestC_count: 1
}
}
])