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 |       Mach SIx Query Optimizing Technology by SuccessWare 90, Inc.       |
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  OVERVIEW:

  The Mach SIx library is a set of functions that interface with SuccessWare
  Replaceable Index Drivers (RDDs) to provide query optimization for selected
  Clipper commands when used with a FOR condition.  Mach SIx optimizes
  queries by following a procedural set of steps that determine the best
  access plan to retrieve the requested set of data.  Mach SIx's primary
  focus is on the existence of index key expressions in the FOR criteria of
  its supported commands and functions.  Using this information, Mach SIx is
  able to directly search the index files to satisfy all or part of the
  query without ever having to access the database.

  Once it becomes necessary to query the physical database, Mach SIx only
  queries the set of records found to meet the condition based on the data
  in the index files.  This means that including just one indexed
  expression, in the FOR condition, has the potential to narrow the scope of
  the query to a very small set of the original file.  This translates to
  incredible speed gains for any optimized command that contains one or more
  index key expressions.  Queries that used to take minutes, now return in
  seconds.  In some cases, you will experience performance increases  that
  are magnitudes above standard Clipper.  It's completely done for you in
  the background.

  All that you need to do, to optimize your existing application with Mach
  SIx, is to include the MACHSIX.CH header file in your source programs,
  recompile, and link with MACHSIX.LIB (and the SIx Driver RDD or HiPer-SIx
  RDD, of course!).  It's that easy.  If Mach SIx is unable to optimize the
  query condition, it simply turns control over to standard Clipper, but
  when it can, you'll see Clipper sail, and sail like it never has before.