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Multiple-Key Access

  1. For some queries, it is advantageous to use multiple indices if they exist.
  2. If there are two indices on deposit, one on bname and one on cname, then suppose we have a query like

     aaaaaaaaaaaa¯select balance

    from deposit

    where bname = ``Perryridge'' and balance = 1000

  3. There are 3 possible strategies to process this query:
  4. The third strategy takes advantage of the existence of multiple indices. This may still not work well if
  5. To speed up multiple search key queries special structures can be maintained.

Osmar Zaiane
Mon Jul 13 13:28:03 PDT 1998