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• The methods are composable. The from fromTime and asOf toTime methods specify the time range.

  • If a user applies the same time limit multiple times such as MultiVersionedKeyQuery.withKey(k).fromfromTime(t1).fromfromTime(t2), then the last one wins (it will be translated to MultiVersionedKeyQuery.withKey(k).fromfromTime(t2)).

  • Defining a query with time range (empty, t1] will be translated into [0, t1] (calling only the from toTime method).
  • Defining a query with time range ([t1, empty) will be translated into [t1, MAX)   (calling only the asOf fromTime method).
  • A query with no specified time range will be translated into [0, MAX). It means that the query will return all the versions of the records with specified key.
• As explained in the javadocs, the query returns all valid records within the specified time range.
  • The fromTime specifies the starting point. There can be records which have been inserted before the fromTime and are valid in the time range. For example, if the record (k,v) has been inserted at time=0, it will be returned by the multi versioned key queries with key=k and fromTime>=0. Obviously, if the record (k,v) becomes tombstone at time=2, then the multi versioned key queries with key=k and fromTime>=2 will not return it any more. In this case, the multi versioned key queries with key=k and fromTime<2 will return the record (k,v) validTo=2.
  • The toTime specifies the ending point. Records that have been inserted at toTime are returned by the query as well.
• The order of the returned records is by default ascending by timestamp. The method withDescendingTimestamps() can reverse the order. Btw, withAscendingTimestamps() method can be used for code readability purpose. 

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