updates - Strategies for finding updated entries in an eventually consistent database -


if have bunch of entries stored in consistent database, there standard strategies how go reliably finding modified entries? of course found "eventually", ok, i'd avoid possible scenarios in never found.

this seems issue should extremely prevalent , therefore expect there standard ways of handling it. unfortunately i'm having quite hard time finding useful it.

the approach i've been thinking tag entries sort of monotonically increasing version number (e.g. timestamp) , querying database entries version number larger highest 1 i've seen far. problem entries might committed (and returned in query) out of order. so, if later update "makes it" given query , earlier 1 doesn't, can't use later one's version number highest i've seen far in next query, otherwise never find earlier update.

if version numbers guaranteed increasing continuously no skipped versions (which difficult achieve in case, might doable), keep around change log 1 entry each change , query "give me versions except x, y, z, ...". change log , associated queries potentially huge (depending on speed @ changes come in relative time-scale on can assume consistency), don't think option.

any thoughts?


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