MapReduce 中的 Golang GlobalSign mgo 查询

Question

import "github.com/globalsign/mgo"job := &mgo.MapReduce{    Map:    "function() { emit(this.name, 1) }",    Reduce: "function(key, values) { return Array.sum(values) }",    Out:    "res",}_, err = c.Find(nil).MapReduce(job, nil)如何将“查询”添加到上面的 golang mgo mapreduce ？参考：https://docs.mongodb.com/manual/core/map-reduce/ https://godoc.org/github.com/globalsign/mgo#MapReduce

Answer 1

设法通过 MongoDb 官方 godriver 完成此任务

"go.mongodb.org/mongo-driver/bson"

"go.mongodb.org/mongo-driver/mongo"

"go.mongodb.org/mongo-driver/mongo/options"

par := bson.D{

    {"mapreduce", "audit"},

    {"map", " function() { emit( this.name , 1 ); }"},

    {"reduce", "function(key, arr) { return Array.sum(arr); }"},

    {"out", "mr3"},

    {"query", bson.D{{"status", "SUCCESS"}}},

}

sr := db.RunCommand(nil, par)

Answer 2

MapReduce是 Find 返回的 Query 结构的函数。因此，为了将 MapReduce 应用于查询结果，只需将查询文档添加到 find 函数中即可：

c.Find(query).MapReduce(job,result)