使用github.com/icza/minquery直接查询第3页的值

Question

I wanna confirm the right way to get skip(3) values using minquery, 1. foreach skip, get 1,2,3 page data, then return the 3rd value? or 2. use a way to get the cursor of skip(3). if the 2rd is right, how to get the cursor of skip(3) page? Thanks.

Answer 1

You can't skip documents directly using github.com/icza/minquery. The purpose of minquery is to not have to use Query.Skip() (because that becomes less efficient when the number of "skippable" documents grows). The only way to skip 3 documents is to query for more than 3, and throw away the first 3.

minquery is for cases where you don't have to skip the initial documents. minquery requires you to iterate over the documents, and acquire the cursor that encodes the index entry of the last returned document (this cursor is returned to you by MinQuery.All()). When you need the next page, you have to use the cursor you acquired in the previous query, and then it can list subsequent documents without having to skip anything, because the encoded index entry can be used to jump right where the last query finished listing documents.

Think of GMail: you can always jump just to the next (and previous) page of emails, but you have no way of "magically" jumping to the 10th or 100th page: GMail uses the same mechanism under the hood.