The operator exists...in returns TRUE if
- for at least one element variable1 in list1
- for at least one element variable2 in list2
- etc.
the query boolean is true.
Prototype
boolean <-- exists variable1 in list1 [, variable2 in list2]* : boolean Examples
exists $d in (top DATE within file $myfile): text($d) match "1992"; TRUENote that the evaluation stops at the first tuple for which boolean is true. The computation can be expensive for large lists, since in the worst case, the entire cartesian product of list1, list2, etc. is computed.