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Databases Mongo Basics Go Further With Mongo Doing More With Queries in Mongo

Posted by Kirby Simmons
Kirby Simmons
5,197 Points

JS solution to get all unique keys from a collection

Object.keys(db.posts.find().toArray().reduce((obj, val) => { return Object.assign({},obj,val)}, {}))
Vitaly Khe
Vitaly Khe
7,160 Points
Vitaly Khe
Vitaly Khe
7,160 Points

Very elegant. Thank you! I would have done that with following code:

db.posts.find({},{id: false}).toArray()
  .reduce((arr, obj) => {
    return arr.concat( Object.keys(obj) )
  }, [])
  .filter((item, index, arr) => {
    return arr.indexOf(item) === index;
  })
;