0
我有我的MongoDB實例,看起來像下面拆分和彙總數從陣列
{
...
regions: ["Region-West", "Region-HC"],
care_levels: ["Memory Care"],
...
}
{
...
regions: ["Region-West", "Region-SC"],
care_levels: ["Physical Rehab"],
...
}
{
...
regions: ["Region-East", "Region-NC"],
care_levels: ["Physical Rehab"],
...
}
的地區和護理水平的文檔都是一個字符串數組。我想執行由特定區域集和care_levels映射的文檔數。例如 -
Region-East, Physical Rehab => 20
Region-East, Memory Care => 20
Region-West, Memory Care => 30
我運行下面的查詢
db.incidents.aggregate([
{$match:
{"care_levels": { $size: 1, $in: ["Memory Care", "Physical Rehab"] }},
},
{ "$group": {
"_id": {
"regions": "$regions",
"care_levels": "$care_levels",
},
"incidentCount": { "$sum": 1 }
}},
])
和我得到的結果作爲
{ "_id" : { "regions" : [ "Region-East", "Region-HC" ], "care_levels" : [ "Memory Care" ] }, "incidentCount" : 2409 }
{ "_id" : { "regions" : [ "Region-East", "Region-HC" ], "care_levels" : [ "Physical Rehab" ] }, "incidentCount" : 2459 }
{ "_id" : { "regions" : [ "Region-East", "Region-SC" ], "care_levels" : [ "Memory Care" ] }, "incidentCount" : 2504 }
{ "_id" : { "regions" : [ "Region-West", "Region-HC" ], "care_levels" : [ "Memory Care" ] }, "incidentCount" : 2382 }
{ "_id" : { "regions" : [ "Region-West", "Region-HC" ], "care_levels" : [ "Physical Rehab" ] }, "incidentCount" : 2475 }
{ "_id" : { "regions" : [ "Region-East", "Region-SC" ], "care_levels" : [ "Physical Rehab" ] }, "incidentCount" : 2478 }
{ "_id" : { "regions" : [ "Region-South", "Region-HC" ], "care_levels" : [ "Physical Rehab" ] }, "incidentCount" : 2405 }
{ "_id" : { "regions" : [ "Region-West", "Region-SC" ], "care_levels" : [ "Memory Care" ] }, "incidentCount" : 2490 }
{ "_id" : { "regions" : [ "Region-West", "Region-SC" ], "care_levels" : [ "Physical Rehab" ] }, "incidentCount" : 2433 }
{ "_id" : { "regions" : [ "Region-South", "Region-HC" ], "care_levels" : [ "Memory Care" ] }, "incidentCount" : 2465 }
我要過濾掉,我不關心的地區。在這種情況下,我不希望區域SC和區域HC的分割以及區域西/東/南的計數應該是區域SC和區域HC分割的值的總和。
具體來說,在這種情況下,我想要的值
Region-East, Memory Care => (2409 + 2504)
Region-West, Memory Care => (2382 + 2490)
我如何通過進一步聚集實現這一目標?