diff --git a/src/backend/commands/analyze.c b/src/backend/commands/analyze.c
index 5fcedd7..9ac7122 100644
*** a/src/backend/commands/analyze.c
--- b/src/backend/commands/analyze.c
*************** compute_distinct_stats(VacAttrStatsP sta
*** 2049,2056 ****
  
  		if (nmultiple == 0)
  		{
! 			/* If we found no repeated values, assume it's a unique column */
! 			stats->stadistinct = -1.0;
  		}
  		else if (track_cnt < track_max && toowide_cnt == 0 &&
  				 nmultiple == track_cnt)
--- 2049,2059 ----
  
  		if (nmultiple == 0)
  		{
! 			/*
! 			 * If we found no repeated non-null values, assume it's a unique
! 			 * column; but be sure to discount for any nulls we found.
! 			 */
! 			stats->stadistinct = -1.0 * (1.0 - stats->stanullfrac);
  		}
  		else if (track_cnt < track_max && toowide_cnt == 0 &&
  				 nmultiple == track_cnt)
*************** compute_scalar_stats(VacAttrStatsP stats
*** 2426,2433 ****
  
  		if (nmultiple == 0)
  		{
! 			/* If we found no repeated values, assume it's a unique column */
! 			stats->stadistinct = -1.0;
  		}
  		else if (toowide_cnt == 0 && nmultiple == ndistinct)
  		{
--- 2429,2439 ----
  
  		if (nmultiple == 0)
  		{
! 			/*
! 			 * If we found no repeated non-null values, assume it's a unique
! 			 * column; but be sure to discount for any nulls we found.
! 			 */
! 			stats->stadistinct = -1.0 * (1.0 - stats->stanullfrac);
  		}
  		else if (toowide_cnt == 0 && nmultiple == ndistinct)
  		{
*************** compute_scalar_stats(VacAttrStatsP stats
*** 2753,2759 ****
  		else
  			stats->stawidth = stats->attrtype->typlen;
  		/* Assume all too-wide values are distinct, so it's a unique column */
! 		stats->stadistinct = -1.0;
  	}
  	else if (null_cnt > 0)
  	{
--- 2759,2765 ----
  		else
  			stats->stawidth = stats->attrtype->typlen;
  		/* Assume all too-wide values are distinct, so it's a unique column */
! 		stats->stadistinct = -1.0 * (1.0 - stats->stanullfrac);
  	}
  	else if (null_cnt > 0)
  	{