What is different between id and _id

[thanhlmm]

Overview of the Issue

I can see we can use both id or _id to query some document. But with one is refer to? I checked out in my monbodb data that it only store _id. Then id is maped base on _id ? If yes, how to generate id from _id

[tothandras]

Hey @nlug, _id is the mongoose identifier and id is a unique identifier across all types which is also encodes the model type. It was needed for the Relay support to have globally unique ids. https://github.com/RisingStack/graffiti-mongoose/blob/1d1f6d1d3d18c52da969ef9694c8b6a619679170/src/query/query.js#L99