/*
** Example of how to build a save set.
*/
#include <mi.h>
 
mi_integer
build_saveset( MI_CONNECTION *conn)
   {
   MI_SAVE_SET  *ss;
   MI_ROW       *row;
   MI_ROW       *rowss;
 
   mi_integer   error;
 
   ss = mi_save_set_create( conn );
 
   if( NULL == ss )
      {
      fprintf(stderr, "could not create save set\n");
      return (-1);
      }
/* insert each row into the save set */
 
   while( NULL != ( row = mi_next_row( conn, &error ) ) )
      {
 
      rowss = mi_save_set_insert( ss, row );
 
      if( NULL == rowss )
         {
         mi_db_error_raise( conn, MI_MESSAGE,
            "Could not insert into save set\n" );
         return (-1);
         }
      else
         {
         ; /* continue */
         }
 
      } /* END WHILE */
 
   if (error == MI_ERROR)
	 {
	 mi_db_error_raise( conn, MI_MESSAGE, "could not get next row\n" );
	 return(-1);
	 }
   else
      {
      ; /* continue */
      }
 
   /* Print out message to informix log file */
 
   fprintf(stderr, "%d rows inserted in save set\n",
      mi_save_set_count(ss));
 
   get_saveset_data(ss);
 
   error =  mi_save_set_destroy( ss );
 
   if( MI_ERROR == error )
      {
      mi_db_error_raise( conn, MI_MESSAGE, "could not destroy save set\n" );
      return (-1);
      }
   else
      {
      ; /* continue */
      }
 
   return(0);
   }

When a row is obtained, its values are extracted using an mi_value() loop as demonstrated in "Example: get_data()". Functions also exist for retrieving the number of rows in a save set ((mi_save_set_count()) and determining if a given row is a member of a save set (mi_save_set_member()).

The following function, get_saveset_data(), traverses the save set:

/*
** Get Save Set Data Example
*/
#include "mi.h"
 
mi_integer
get_saveset_data( MI_SAVE_SET * ss)
   {
   MI_ROW          *row;
   MI_ROW_DESC     *rowdesc;
   mi_integer      error;
   mi_integer      numcols;
   mi_integer      i;
   char            *colname;
   mi_integer      collen;
   char            *colval;
 
   /* get the first row from the save set */
   row = mi_save_set_get_first(ss, &error);
      if (error == MI_ERROR)
      {
      fprintf(stderr, "could not get first row from save set\n");
      return(-1);
      }
 
   /* get the description of the row */
   rowdesc = mi_get_row_desc(row);
 
   /* get the number of columns in the row */
   numcols = mi_column_count(rowdesc);
 
   /* print the column names */
   for (i = 0; i < numcols; i++)
      {
      colname = mi_column_name(rowdesc, i);
      fprintf(stderr, "%s\t", colname);
      }
 
   fprintf(stderr, "\n\n");
 
   /* for each column */
      for (i = 0; i < numcols; i++)
      {
      switch( mi_value( row, i, &colval, &collen ) )
         {
         case MI_ERROR:
            fprintf(stderr, "\ncannot get value\n");
            return(-1);
         case MI_NULL_VALUE:
            colval = "NULL";
            break;
         case MI_NORMAL_VALUE:
            break;
         default:
            fprintf(stderr, "\nunknown value\n");
            return(-1);
         }
 
      fprintf(stderr, "%s\t", colval);
      }
 
   /* for each row */
      while ((row = mi_save_set_get_next(ss, &error)) != NULL)
      {
      if (error == MI_ERROR)
         {
         fprintf(stderr, "\ncould not get next row");
         return (-1);
         }
 
      /* for each column */
      for (i = 0; i < numcols; i++)
         {
         switch(mi_value(row, i, &colval, &collen))
            {
            case MI_ERROR:
               fprintf(stderr, "\ncannot get value\n");
               return(-1);
            case MI_NULL_VALUE:
               colval = "NULL";
               break;
            case MI_NORMAL_VALUE:
               break;
            default:
               fprintf(stderr, "\nunknown value\n");
			      break;
            }
 
         fprintf(stderr, "%s\t", colval);
         }
      fprintf(stderr, "\n");
      }
 
   fprintf(stderr, "\n");
   return(1);
   }