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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