diff options
Diffstat (limited to 'doc/src')
| -rw-r--r-- | doc/src/sgml/func.sgml | 18 |
1 files changed, 14 insertions, 4 deletions
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml index 8d7d9a2f3e8..a6d79765c1a 100644 --- a/doc/src/sgml/func.sgml +++ b/doc/src/sgml/func.sgml @@ -1824,13 +1824,23 @@ SELECT NOT(ROW(table.*) IS NOT NULL) FROM TABLE; -- detect at least one null in which <parameter>operand</parameter> falls in a histogram having <parameter>count</parameter> equal-width buckets spanning the range <parameter>low</parameter> to <parameter>high</parameter>. - Returns <literal>0</literal> + The buckets have inclusive lower bounds and exclusive upper bounds. + Returns <literal>0</literal> for an input less + than <parameter>low</parameter>, or <literal><parameter>count</parameter>+1</literal> for an input - outside that range. + greater than or equal to <parameter>high</parameter>. + If <parameter>low</parameter> > <parameter>high</parameter>, + the behavior is mirror-reversed, with bucket <literal>1</literal> + now being the one just below <parameter>low</parameter>, and the + inclusive bounds now being on the upper side. </para> <para> <literal>width_bucket(5.35, 0.024, 10.06, 5)</literal> <returnvalue>3</returnvalue> + </para> + <para> + <literal>width_bucket(9, 10, 0, 10)</literal> + <returnvalue>2</returnvalue> </para></entry> </row> @@ -1842,8 +1852,8 @@ SELECT NOT(ROW(table.*) IS NOT NULL) FROM TABLE; -- detect at least one null in <para> Returns the number of the bucket in which <parameter>operand</parameter> falls given an array listing the - lower bounds of the buckets. Returns <literal>0</literal> for an - input less than the first lower + inclusive lower bounds of the buckets. + Returns <literal>0</literal> for an input less than the first lower bound. <parameter>operand</parameter> and the array elements can be of any type having standard comparison operators. The <parameter>thresholds</parameter> array <emphasis>must be |