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      D_SETPAGES

SUMMARY
   d_setpages(dbpages,ovpages)
   int dbpages;
   int ovpages;

ARGUMENTS

   dbpages       The number of pages for the database cache.

   ovpages       The number of pages for the transaction overflow cache.

DESCRIPTION
   Function d_setpages is used to specify to the db_VISTA runtime system how
   many pages to alocate for the database and transaction overflow virtual
   memory caches. The default values are 16 database pages and 4 overflow
   virtual memory pages. This function must be called prior to d_open.

   Best performance can be achieved by using as high a dbpages value as you
   have memory to support. The db_VISTA runtime utilizes a fast binary search
   to determine if page is in the cache. Thus, if db pages were initially set
   to 256, it would take db_vista no more than 8 comparisons to locate a page
   in the cache.

   The ovpages value should be keep low (at least 4 but generally less than
   10) unless you application has many very long and complex transactions
   which will split over into the transaction overflow file.

   If you do not have enought memory to support the specified number of pages,
   function d_open will return status S_NOMEMORY, in which case you should
   reduse the specified amount any try again.


CURRENCY CHANGES
   None

RETURN CODES

   -20  S_SETPAGES     d_setpages was called after the database was opened.

EXAMPLE


   d_setpages(258,8);
   d_open("tims","s");
    ..

See Also: d_open d_setfiles

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