使用nodejs链码从hyperledger fabric v 1.4中的链码获取记录时如何设置偏移量和限制？

Question

I have more than 500 records in my blockchain network and i want to write a chaincode for the pagination on frontend. I have used getQueryResultWithPagination and getStateByRangeWithPagination but my concern is that i want to fetch records starting from 90th to 100th means 10 records but not starting from beginning neither i want to fetch the whole record. My chaincode is written in nodejs. I'm stuck on this and would really appreciate the community to give me their valuable suggestions.

Answer 1

Are you looking for directly jumping to a page if so, then its not possible. One drawback of the linked list style pagination is that you can't pre-compute the rows for a particular page from the page number and the rows per page. Jumping to a specific page doesn't really work.

Just see here for the reference: https://docs.couchdb.org/en/stable/ddocs/views/pagination.html

Answer 2

getQueryResultWithPagination of course only works with CouchDB ... so when using the CouchDB query language you should be able to specify the skip parameter in your actual query. Note that per the documentation, the limit parameter is not honored as the page size parameter is used:

If a pageSize is specified using the paginated query APIs (GetStateByRangeWithPagination(), GetStateByPartialCompositeKeyWithPagination(), and GetQueryResultWithPagination()), a set of results (bound by the pageSize) will be returned to the chaincode along with a bookmark. The bookmark can be returned from chaincode to invoking clients, which can use the bookmark in a follow on query to receive the next “page” of results.

Of course to build a front-end client which pages through results, you need to pass both the pageSize and bookmark parameters to getQueryResultWithPagination and your chain code function will need to return the bookmark to the caller so that it can be passed in to fetch the next page of results.

Answer 3

如果有人有跳转分页的示例代码，请帮忙？