<IndexSearchCond>::=IndexSingleCond
LogicalOperator(<IndexSearchCond>,<IndexSearchCond>)
compress(Attr_name,<IndexSearchCond>)
IndexSingleCond::=RangeSearch Attr_name ComparisonOperator Attr_value Attr_name= concat(String,*) not_exist(Attr_name) is_null(Attr_name)
String::= STRING
Attr_name::= ATOM
ComparisonOperator::= =< < > >= =
LogicalOperator::= and or dif
RangeSearch::= range(Attr_name,Attr_value1,Attr_value2) etc.
Attr_value::= INTEGER STRING