/TypeScript/Mongo count elements in array

Mongo count elements in array

> db.mycollection.insert({'foo':[1,2,3,4]})
> db.mycollection.insert({'foo':[5,6,7]})

> db.mycollection.aggregate([{$project: { count: { $size:"$foo" }}}])
{ "_id" : ObjectId("5314b5c360477752b449eedf"), "count" : 4 }
{ "_id" : ObjectId("5314b5c860477752b449eee0"), "count" : 3 }

Source: stackoverflow.com

Mongo count elements in array

{ $size: <expression> }

Source: docs.mongodb.com

Mongodb count array size

db.inventory.aggregate([
   {
      $project: {
         item: 1,
         numberOfColors: { $cond: { if: { $isArray: "$colors" }, then: { $size: "$colors" }, else: "NA"} }
      }
   }
] )

Source: docs.mongodb.com

Similar codes

2 votes266 views1 answer
Reactive forms get value of control
TypeScript
0 vote292 views1 answer
Storing user name and password ofr hosts in ansible playbooks
TypeScript
1 vote255 views1 answer
How to count positive elements numpy
TypeScript
7 votes256 views3 answers
How to make a rounded button
TypeScript
0 vote253 views1 answer
Vscode tsc.ps1 command not loaded
TypeScript
2 votes261 views1 answer
Ts sorting
TypeScript
11 votes269 views3 answers
Property 'active' has no initializer and is not definitely assigned in the constructor.ts(2564)
TypeScript
8 votes294 views6 answers
Google fonts flutter
TypeScript
0 vote269 views1 answer
Create an array for looping typescript
TypeScript
0 vote260 views1 answer
MInus points of exploration
TypeScript