mongodbrelation

README

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What is this module for?

this module is used for using mongodb as sql database we can perform joins among different collections of our mongodb database

How do I get set up?

 npm install mongodbrelation

NEW FEATUES I AM WORKING ON

• Nested Joins

Who do I talk to?

• [e-mail]

FEATURES AVAILABLE

PERFORM JOINS AMONG DIFFERENT COLLECTIONS OF MONGODB

USAGE

<!-- authors collection -->
  [
   {"_id": 100, "name": "author 1"},
   {"_id": 102, "name": "author 2"},
   {"_id": 103, "name": "author 3"}
  ]

 <!-- blogs collection -->
   [
    {"_id":1, "blogname": "blog1", "description":" blog description 1", "authorid": 100},
    {"_id":2, "blogname": "blog2", "description":" blog description 2", "authorid": 100}
   ]

ONE_TO_ONE

let take an example of

ONE_TO_ONE i.e one blog belongs to one author

so we need a query like get all blogs and join the author in blog document.

here parent is blog and child is author since author will be appended to blog
condition: null (since we want all the blogs)
joinCollectionName: authors (since we will join author to blogs)
joinFieldName: authorid (since parent is blog the key that is present in child is authorid)
foreignFieldName: _id (authorid can be mapped to _id with author)
aliasname: authoralias (or what ever you prefer for the aliasname you can provide any string)
outputfields: null since we want to select all
typeofJoin: ONE_TO_ONE

IN Action for ONE_TO_ONE

const mongodbrelation = require('mongodbrelation');
let query = mongodbrelation.joinedQuery(null,"authors", "authorid", "_id", "authoralias", null, "ONE_TO_ONE"); 
let dbquery = BlogModel.aggregate(query); // where BlogModel is mongoose Model Object
dbquery.exec(function(err, result) {
  console.log(result);
})

CONSOLE OUTPUT

[
  {
    "_id": 1,
    "blogname": "blog1",
    "description": " blog description 1",
    "authorid": 100,
    "createdAt": "2018-03-12T11:07:05.256+0000",
    "updatedAt": "2018-03-12T11:07:05.256+0000",
    "__v": 0,
    "authoralias": {
      "_id": 100,
      "name": "author 1",
      "createdAt": "2018-03-12T11:07:05.256+0000",
      "updatedAt": "2018-03-12T11:07:05.256+0000",
      "__v": 0
    }
  },
  {
    "_id": 2,
    "blogname": "blog2",
    "description": " blog description 2",
    "authorid": 100,
    "createdAt": "2018-03-12T11:07:05.256+0000",
    "updatedAt": "2018-03-12T11:07:05.256+0000",
    "__v": 0,
    "authoralias": {
      "_id": 100,
      "name": "author 1",
      "createdAt": "2018-03-12T11:07:05.256+0000",
      "updatedAt": "2018-03-12T11:07:05.256+0000",
      "__v": 0
    }
  }
]

ONE_TO_MANY

let take an example of

ONE_TO_MANY i.e one author can write may blogs

so we need a query like get author where authorid = 100 and append his/her blogs in blogalias

here parent is blog and child is author since author will be appended to blog
condition: {"_id":100} (since we want the author where _id: 100)
joinCollectionName: blogs (since we will join blogs to authors)
joinFieldName: _id (since parent is author and _id is present in child as collection blogs as authorid)
foreignFieldName: authorid (authorid can be mapped to _id with authors collection)
aliasname: blogalias (or what ever you prefer for the aliasname you can provide any string)
outputfields: null since we want to select all
typeofJoin: ONE_TO_MANY

IN Action for ONE_TO_MANY

  const mongodbrelation = require('mongodbrelation');
  var query = mongodbrelation.joinedQuery({_id: 100},"blogs", "_id", "authorid", "blogalias", null, "ONE_TO_MANY"); 
  let dbquery = AuthorsModel.aggregate(query); // where AuthorsModel is mongoose Model Object
  dbquery.exec(function(err, result) {
    console.log(result);
  })

CONSOLE OUTPUT

{
  "_id": 100,
  "name": "author 1",
  "createdAt": "2018-03-12T11:07:05.256+0000",
  "updatedAt": "2018-03-12T11:07:05.256+0000",
  "__v": 0,
  "blogalias": [
    {
      "_id": 1,
      "blogname": "blog1",
      "description": " blog description 1",
      "authorid": 100,
      "createdAt": "2018-03-12T11:07:05.256+0000",
      "updatedAt": "2018-03-12T11:07:05.256+0000",
      "__v": 0
    },
    {
      "_id": 2,
      "blogname": "blog2",
      "description": " blog description 2",
      "authorid": 100,
      "createdAt": "2018-03-12T11:07:05.256+0000",
      "updatedAt": "2018-03-12T11:07:05.256+0000",
      "__v": 0
    }
  ]
}

Contribution guidelines

• Writing tests
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• Other guidelines