MDX Function and Operator Reference - Professional SQL Server Analysis Services 2005 with MDX - page 1042

Note that although this function in theory may return multiple ancestors,
the ancestors must be from the same hierarchy and the same level.
See also: Ancestor (), Ascendants (), Descendants (), .Children
expr1 AND expr2 Returns: Boolean Standard
The AND operator returns true if both expr1 and expr2 are true, and false
otherwise. In Microsoft Analysis Services, if expr1 is false, then expr2 is
not evaluated (there is no need to; the result is guaranteed to be false);
this may be relevant when expr2 could have side effects or is costly to
evaluate.
Ascendants ( member ) Returns: set Extension: AS2005, AS2000
This function returns the full set of ancestors for the given member all the
way up to the root of the hierarchy or dimension. The ancestors are
ordered from the bottom up, so that parents follow children. The given
member is included in the set. It is very useful in queries when you want
to include all higher level totals for a given member or set of members.
The behavior of Ascendants () is shown in Figure A-2 .
Figure A-2: Behavior of Ascendants ().
Note that the order of the resulting set must be changed by using Hier-
archize () to get a top-down ordered set before being used in conjunction
with any of the drill-related or VisualTotals () functions.
See also: Ancestor (), Ancestors (), Descendants (), .Children
Avg ( set [, numeric expression ]) Returns: number Standard