diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 8d7d9a2f3e8..11676b63c82 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -1824,13 +1824,24 @@ SELECT NOT(ROW(table.*) IS NOT NULL) FROM TABLE; -- detect at least one null in
which operand falls in a histogram
having count equal-width buckets spanning the
range low to high.
- Returns 0
+ The buckets have inclusive lower bounds, and therefore exclusive
+ upper bounds.
+ Returns 0 for an input less
+ than low,
or count+1 for an input
- outside that range.
+ greater than or equal to high.
+ If low > high,
+ the behavior is mirror-reversed, with bucket 1
+ now being the one just below low, and the
+ inclusive bounds now being on the upper side.
width_bucket(5.35, 0.024, 10.06, 5)
3
+
+
+ width_bucket(9, 10, 0, 10)
+ 2
@@ -1842,8 +1853,8 @@ SELECT NOT(ROW(table.*) IS NOT NULL) FROM TABLE; -- detect at least one null in
Returns the number of the bucket in
which operand falls given an array listing the
- lower bounds of the buckets. Returns 0 for an
- input less than the first lower
+ inclusive lower bounds of the buckets.
+ Returns 0 for an input less than the first lower
bound. operand and the array elements can be
of any type having standard comparison operators.
The thresholds array must be