如何使用猫鼬和异步瀑布模型在 MongoDb 中存储数据
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【中文标题】如何使用猫鼬和异步瀑布模型在 MongoDb 中存储数据【英文标题】：How to store data in MongoDb using mongoose and async waterfall model 【发布时间】：2018-03-11 01:54:17 【问题描述】：您好，我是 node 新手，我正在尝试将数据保存在 mongoose 中。问题是有 3 个集合 Units、Building 和 Section。 建筑的架构是：
var buildingsSchema=new Schema(
buildingname:String,
status:String
);
Section 的架构是：
var sectionsSchema=new Schema(
section_type:String,
buildings: type: Schema.Types.ObjectId, ref: 'buildings' ,
status:String
);
单位的架构是：
var unitsSchema=new Schema(
unit_type:String,
unit_num:String,
unit_ac_num:Number,
buildings: type: Schema.Types.ObjectId, ref: 'buildings' ,
sections: type: Schema.Types.ObjectId, ref: 'sections' ,
shares:Number
);
在 Section 中有 Building 的 Id，在 Units 中有 Building 和 Section 的 Id's
现在我已经使用xlsx 插件将上传的 excel 文件转换为 json 格式：-
var wb = XLSX.readFile("uploads/xls/" + req.file.filename);
data = XLSX.utils.sheet_to_json(wb.Sheets[wb.SheetNames[0]], header:1);
并将其映射到 json 对象并保存我正在使用 异步瀑布模型
for (var index = 1; index < data.length - 1 ; index++)
var ele= data[index];
// console.log(ele);
var d = // this is an object which will hold data
record_id: ele[0],
residenceone_unit_id : ele[1],
official_unit_id: ele[2],
building: ele[3],
unit_type : ele[4],
section: ele[5],
shares: ele[6],
unit_style : ele[7]
// console.log(d);
var unt = new Units(); // to save units
unt =
unit_type: d.unit_type,
unit_num: d.residenceone_unit_id,
unit_ac_num: d.official_unit_id,
buildings: '', // empty because need to put id of that particular building
sections: '', // empty because need to put id of that particular sections
shares:d.shares
async.waterfall([
function (callback)
// find building first
Buildings.findOne(buildingname : ele.building)
.exec(function (err,doc)
if (err)
return callback(err);
// if no building then save one
else if (!doc)
// console.log("Building is going to save")
var build = new Buildings();
build.buildingname = d.building;
build.status = "active";
build.save(function (err,dc)
if (err)
return callback(err);
else
// assign id of building to unit
unt.buildings = dc._id ;
callback(null);
)
else
// if building is there then no need to save assign id of it to units
// console.log("Building already exists;")
unt.buildings = doc._id ;
// execute second function
callback(null);
// callback(null);
)
,
function (callback)
// same as building find section of that building first with building Id and section type
Sections.findOne(buildings : unt.buildings,section_type: d.section)
.exec(function (err,doc)
if (err)
return callback(err);
if (!doc)
// if no section of that building is there then save one
// console.log("Section needs to be save")
var sect = new Sections();
sect.section_type = d.section;
sect.buildings = unt.buildings;
sect.status = "active";
sect.save(function (err,dc)
if (err)
return callback(err);
else
// assign its id to unit
// console.log("Section is saved")
unt.sections = dc._id;
// execute third function
callback(null);
)
else
// if there is section of that building id is available than assign id to units
// console.log("Section already exists");
unt.sections = doc._id;
// execute third function
callback(null);
)
,
function (callback)
// there is no need to seaarch just need to save unit
// console.log("Units is going to save")
// console.log(unt);
unt.save(function (err, doc)
if (err)
else if (doc)
// console.log("Unit Saved");
// console.log(doc);
)
])
它可以工作，但每次都不是在 mongodb 中搜索数据，而是每次都保存。如果在 mongodb 中保存单位的任何其他方法对我有很大帮助，重复是主要问题。
【问题讨论】：
嗨，我认为您的问题是这样的。 Buildings.findOne(buildingname : ele.building) ele.building 不存在您正在搜索未定义您需要使用 d.building 兄弟，它工作正常，只是问题是数据被一次又一次地插入，而我的实际数据来自数组 您应该使用async.eachSeries()（或者可能是async.eachLimit），而不是使用for (var index = 1; ...)。
好吧，我试着让您知道 ROBERTKLEP 先生
我试过了，但它是 console.log(units) 然后在找到一个在建筑中的文件之后
【参考方案1】：
首先我保存了建筑物和部分：
async.every(uniqueSection,function (uS,callback)
if (uS != undefined)
console.log(uS);
Buildings.findOne(buildingname:uS.building, function (err,doc)
if (doc)
// console.log(doc);
Sections.findOne(buildings:doc._id,section_type:uS.section,function (er,sd)
if (sd)
// then dont save
console.log(sd);
if (er)
console.log(er);
if (!sd)
// then save
var sect = new Sections();
sect.buildings = doc._id;
sect.section_type = uS.section;
sect.status = 'active';
sect.save(function (err,st)
if(err) console.log(err);
console.log(st);
)
)
if (!doc)
if (uS.building != undefined)
var building = new Buildings();
building.buildingname = uS.building;
building.status = "active";
building.save(function (er,dc)
if (dc)
// console.log(dc);
Sections.findOne(buildings:dc._id,section_type:uS.section,function (er,sd)
if (sd)
// then dont save
console.log(sd);
if (er)
console.log(er);
if (!sd)
// then save
var sect = new Sections();
sect.buildings = dc._id;
sect.section_type = uS.section;
sect.status = 'active';
sect.save(function (err,st)
if(err) console.log(err);
console.log(st);
)
)
if (er)
console.log(er);
)
if (err)
console.log(err);
)
)
然后我保存了 Units ：
async.waterfall([
function(callback)
Buildings.findOne(buildingname:d.building, function (err,doc)
if (doc)
buildingId = doc._id;
callback(null, doc);
if (err)
console.log(err);
)
,
function(doc,callback)
Sections.findOne(buildings: buildingId,section_type:d.section,function (er,sd)
if (sd)
sectionId = sd._id;
callback(null,doc,sd);
if (er)
console.log(er);
)
,
function (bld,st,callback)
var s = d.shares.replace(",","");
var unit =
unit_type: d.unit_type,
unit_num: d.residenceone_unit_id,
unit_ac_num: d.official_unit_id,
buildings: bld._id,
sections: st._id,
shares: s
Units.findOne(unit,function (err,unt)
if (err)
console.log(err);
if(unt)
console.log(unt)
if (!unt)
var units = new Units();
units.unit_type = d.unit_type;
units.unit_num = d.residenceone_unit_id;
units.unit_ac_num = d.official_unit_id;
units.buildings = bld._id;
units.sections = st._id;
units.shares = s;
units.save(function (er,doc)
if (er) console.log(er);
console.log(doc);
)
)
], function(err)
console.log(err)
);
【讨论】：
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