Mongodb find() 查询中的限制字段不起作用 [英] Limit Field in Mongodb find() query not working

问题描述

我有一个包含以下字段的 MongoDB 数据库:

I have a MongoDB database withe the following fields:

idSite: 3
parentHash: "zz"
siteDesc: "Second Site"
siteHash: "ab"
siteLevel: "1"
siteName: "Riotech"
siteType: "Company"

idSite: 4
parentHash: "zz"
siteDesc: "Oregon City Site"
siteHash: "aa"
siteLevel: "1"
siteName: "iTi"
siteType: "Company"

我想编写一个带有投影的查询，将结果限制为一个字段的数据集，parentHash.当我编写以下查询时:Sites.find({"siteHash":"aa"},{parentHash:1}).

I want to write a query with a projection that limits the result to a dataset of one field, parentHash. When I write the following query: Sites.find({"siteHash":"aa"},{parentHash:1}).

我得到以下结果:

idSite: 4
parentHash: "zz"
siteDesc: "Oregon City Site"
siteHash: "aa"
siteLevel: "1"
siteName: "iTi"
siteType: "Company"

我试过用双引号和单引号包装字段名称，不带引号.我尝试将所有其他字段的返回状态定义为 false.一切都会返回完整的文档.

I have tried wrapping field names with double and single quotes, without quotes. I have tried defining the return status of all the other fields as false. Everything returns the full document.

推荐答案

我觉得应该是 Sites.find({"siteHash":"aa"},{fields: {parentHash:1}});http://docs.meteor.com/#/full/find

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