8月3日 分布式缓存 周五

> db.user02.find()
{ "_id" : ObjectId("5b62bb0686a5a8512ef03997"), "age" : 2 }
{ "_id" : ObjectId("5b63c85397f09e06e3744745"), "name" : "xiyouji", "type" : 1, "price" : 20 }
{ "_id" : ObjectId("5b63c86497f09e06e3744746"), "name" : "hongloumeng", "type" : 1, "price" : 21 }
{ "_id" : ObjectId("5b63c86f97f09e06e3744747"), "name" : "sanguo", "type" : 1, "price" : 22 }
{ "_id" : ObjectId("5b63c87e97f09e06e3744748"), "name" : "shuihu", "type" : 1, "price" : 25 }
> db.user02.aggregate([{$group:{_id:"$type",user02_sum:{"$price"}}}])
2018-08-03T19:10:44.710+0800 SyntaxError: Unexpected token }
> db.user02.aggregate([$group:{_id:"$type",price_sum:{$sum:"$price"}}])
2018-08-03T19:14:16.671+0800 SyntaxError: Unexpected token :
> db.user02.aggregate([{$group:{_id:"$type",price_sum:{$sum:"$price"}}}])
{ "_id" : 1, "price_sum" : 88 }
{ "_id" : null, "price_sum" : 0 }
>
> db.user02.aggregate([{$group:{_id:"$type",user02_sum:{$sum:"$price"}}}])
{ "_id" : 1, "user02_sum" : 88 }
{ "_id" : null, "user02_sum" : 0 }
> db.user02.aggregate([{$group:{_id:"$type",user02_sum:{$avg:"$price"}}}])
{ "_id" : 1, "user02_sum" : 22 }
{ "_id" : null, "user02_sum" : 0 }
> db.user02.aggregate([{$group:{_id:"$type",user02_max:{$max:"$price"}}}])
{ "_id" : 1, "user02_max" : 25 }
{ "_id" : null, "user02_max" : null }
> db.user02.aggregate([{$group:{_id:"$type",user02_min:{$min:"$price"}}}])
{ "_id" : 1, "user02_min" : 20 }
{ "_id" : null, "user02_min" : null }
> db.user02.aggregate([{$group:{_id:"$type",user02_push:{$push:"$price"}}}])
{ "_id" : 1, "user02_push" : [ 20, 21, 22, 25 ] }
{ "_id" : null, "user02_push" : [ ] }
>
> db.user02.aggregate([{$group:{_id:"$type",user02_first:{$push:"$price"}}}])
{ "_id" : 1, "user02_first" : [ 20, 21, 22, 25 ] }
{ "_id" : null, "user02_first" : [ ] }
> db.user02.aggregate([{$group:{_id:"$type",user02_first:{$first:"$price"}}}])
{ "_id" : 1, "user02_first" : 20 }
{ "_id" : null, "user02_first" : null }
> db.user02.aggregate([{$group:{_id:"$type",user02_last:{$last:"$price"}}}])
{ "_id" : 1, "user02_last" : 25 }
{ "_id" : null, "user02_last" : null }

> db.user04.ensureIndex({age:1})

我触及什么，什么就破碎