What affects the size of the index in MongoDB?

Question

I wonder what affects the size of the index. Do the size of indexed field affects the size of index? If i have field "X" and it contains 10letters strings and i have field "Y" and it contains 100letters string and i create on each of them separate indexes, the index on "Y" field will larger than index on "X" field?

Answer 1

Many "things" effect the sie of indexes, from number, size and type of fields to whether the index is unque/sparse etc.

To answer your question directly:

the index on "Y" field will larger than index on "X" field?

Assuming that you have all the "Y" and "X" fields filled in every document in this fashion then the answer will be yes, {Y:1} will be larger than {X:1}.