Not that I know... but are you using DB Dump or DB Tail?
If you're using DB Tail, it stores the last value at $SPLUNK_HOME/var/lib/splunk/persistentstorage/dbx , where each DB Tail configuration has its own directory and it saves the value for the "tailing" process insice state.xml .
If the process failed in the middle or something happen where this file wasn't updated, the next run will insert duplicated entries.
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You can do that... if you build yourself the appropriate visualization, e.g. using D3. The customizability of charts, either built-in or provided by 3rd party apps, does not go as far as you describe.
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