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authorTom Lane2009-01-06 23:46:06 +0000
committerTom Lane2009-01-06 23:46:06 +0000
commit01e050fd2bcbef383911f1ead4c0f3be275e2d08 (patch)
tree1830b63cd83285b69f49dce6ad5d0052920ef630
parent4c3d441e090b18095ef8e2bf8d35e89f8b558dc4 (diff)
Clarify a confusing comment about MCVs vs histogram entries.
Per Nathan Boley.
-rw-r--r--src/backend/commands/analyze.c4
1 files changed, 3 insertions, 1 deletions
diff --git a/src/backend/commands/analyze.c b/src/backend/commands/analyze.c
index 7fa8cee2e1..311397b360 100644
--- a/src/backend/commands/analyze.c
+++ b/src/backend/commands/analyze.c
@@ -2149,7 +2149,9 @@ compute_scalar_stats(VacAttrStatsP stats,
* least 2 instances in the sample. Also, we won't suppress values
* that have a frequency of at least 1/K where K is the intended
* number of histogram bins; such values might otherwise cause us to
- * emit duplicate histogram bin boundaries.
+ * emit duplicate histogram bin boundaries. (We might end up with
+ * duplicate histogram entries anyway, if the distribution is skewed;
+ * but we prefer to treat such values as MCVs if at all possible.)
*/
if (track_cnt == ndistinct && toowide_cnt == 0 &&
stats->stadistinct > 0 &&