SFID: 1469591#
Submitted By: verbguy

We've added "efficient unprepare". The current API
isc_dsql_free_stmt() only supports DSQL_close (which
only closes a named cursor) and DSQL_drop (which
frees the statement handle). This change adds
DSQL_unprepare.

The api addition is:

#define DSQL_close 1
#define DSQL_drop 2
#define DSQL_unprepare 4


Here is the code change for dsql/DStatement.cpp

ISC_STATUS DStatement::freeStatement(ISC_STATUS*
statusVector, int options)
{
 ThreadData thread (statusVector, attachment);

 try
  {
  if (options & (DSQL_close | DSQL_unprepare))
   closeCursor();

  if (options & (DSQL_drop | DSQL_unprepare))
   {
   closeStatement();
   if (options & DSQL_drop)
    delete this;
   }
  }
 catch (OSRIException& exception)
  {
  return exception.copy (statusVector);
  }

 return 0;
}