ios - Infinite scroll and duplicated data -

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i work on mobile app shows stream of data fetched server. app fetches first page 10 items. when user scrolls down, app fetches second page next 10 items (in other words - infinite scroll). problem have when user fetches page number x possible, user b creates new content on server modifies resultset available user a. means if user tries fetch x+1 page, contain previous item(s) "pushed back" new content. how solve it? came out 2 solutions don't know better:

  1. the mobile app remembers ids of shown items , if in next page there item shown, not shown again.
  2. the app remembers date of creation of first item first page. when fetches next pages, additionaly sends date server adds date sql query in order maintain same resultset

what think? better? there better solutions?

update:

imagine have table 'queries' columns 'queries_id' (integer, primary key), 'date_created' (timestamp). query looks this: select * queries order date_created desc. not true date_created date_created increments primary key incremenatation. paginate data spring data using pageable object. problem if new rows created , have date_created newer previous newest row modify resultset.

this happens because pagination based on date_created.
assume query order date_created desc , offset current page.
avoid problem need add last id of previous fetch in query. i.e. queries_id < last_id order date_created .... etc


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