mysql - Best way to check deleted item when doing data synchronization? -


i have system periodically calls api fetch list of attendees event, , store/synchronize attendees in local rdb.

each record has timestamp field can use check updated/new records.

however don't have elegant solution checking deleted records. matching each record id against local db viable way of finding items deleted?

if api returns entire list, start way:

  1. put list table, say, list.
  2. see new via from list left join local using(name) local.name null. (it unclear how timestamp factors in.)
  3. to see deleted, swap table names.

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