Search with mongodb

All we need is an easy explanation of the problem, so here it is.

Im learning mongodb and Im starting the searching commands but looking for an example i found this db.amigos.find({Nombre: "Marisa" },{Nombre:1, Apellidos:2})

What does :1 and :2 means?

How to solve :

I know you bored from this bug, So we are here to help you! Take a deep breath and look at the explanation of your problem. We have many solutions to this problem, But we recommend you to use the first method because it is tested & true method that will 100% work for you.

Method 1

That ",{Nombre:1, Apellidos:2}" part is ‘projection‘, where you tell what fields you want to be in the result. Without it, all fields are included to result.

Normally you use

  • 0 to remove field
  • 1 to include a field

But, any positive value will work as "include field". This example find will return fields _id, Nombre, Apellidos

Field _id is always returned in the result IF it is not especially removed like:

db.amigos.find({Nombre: "Marisa" },{_id:0, Nombre:1, Apellidos:2})

If your projection have only "remove field" clauses, then all other fields are returned, but not those what you list, there

db.amigos.find({Nombre: "Marisa" },{_id:0, Apellidos:0})

So, now every field except _id and Apellidos is returned in the result.

Note: Use and implement method 1 because this method fully tested our system.
Thank you 🙂

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