MDAC 2.5 SDK - OLE DB Programmer's Reference
Chapter 25: MDX Grammar

MDX Tuple Value Expressions

The construct of the tuple value expression is as follows:

<tuple_value_expression> ::= <set>.CURRENTMEMBER
                           | <set>[.ITEM]({<string_value_expression> 
                                       [, <string_value_expression>...]}
                                       | <index>)

The following table describes the tuple value expressions:

Element	Description
<set>.CURRENTMEMBER	Gives the current tuple in <set>. The concept of "currency" occurs in functions such as GENERATE, where the semantics include some form of iteration through tuples of a set.
<set>[.ITEM](<string_expression> [, <string_expression>...] \| <index>)	Returns a tuple from <set>. The <string_expression> [, <string_expression>...] specifies which tuple to retrieve. The <index> value specifies the position of the tuple in <set>. The numbering of the tuples is zero-based.