set 54 contains exactly a certain number of items characterized by the one or more characteristics of the trigger or less than a threshold number of items characterized by the one or more characteristics of the trigger in an embodiment of the present invention the result characteristics based triggering described hereinabove with reference to fig2 supports ordered attributes as mentioned above with reference to fig1 an ordered attribute trigger takes the form of a n 1 n 2 wherein n 1 and n 2 are the lower and upper bounds respectively of the range of values of the attribute ordered attributes commonly include price and date the attribute value pair for any single given item in memory 26 is expressed as a n i e the item typically has only a single value n for the attribute a e g a price of 10 for supporting ordered attributes the method of fig2 includes at an ordered attribute characterization step 80 further characterizing those characteristics of set 58 which are ordered as mentioned above set 58 is produced at result set characterization step 56 such further characterization results in a set 82 of range characteristics and corresponding counts of items from result set 54 that map to the range in other words set 82 includes one or more attribute value ranges a n 1 n 2 and corresponding counts at threshold comparison step 60 result processor 22 compares the counts of each attribute value range of set 82 to thresholds 62 attribute value ranges having a count that exceeds an appropriate.