How does MongoDB control the viewing of secondary indexes?

Question

By default, MongoDB creates an index in the _id file in the document. But when I provide an additional index (secondary, like in InnoDB from MySQL?) And requests it after, the engine scans it and then selectively scans the _id index to get the offset documments?

I am confused because when a splinter appears, I’m right, each piece has its own indices and there will be many random reads for each request?

Answer 1

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