from X3H2-97-030 (I think)
c) Let P be any row of TS and let Q be any other row of TS,
and let PVi and QVi be the values of Ki in these rows,
respectively. The relative position of rows P and Q in the
result is determined by comparing PVi and QVi according to
the rules of Subclause 8.2, "<comparison predicate>", where
the <comp op> is the applicable <comp op> for Ki, with the
following special treatment of null values. Whether a sort
key value that is null is considered greater or less than
a non-null value is implementation-defined, but all sort
key values that are null shall either be considered greater
than all non-null values or be considered less than all non-
null values. PVi is said to precede QVi if the value of the
<comparison predicate> "PVi <comp op> QVi" is true for the
applicable <comp op>.
And if anyone can follow that.......
Adrian
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