matchfield is the field containing the discrete numeric values to be linked to intervals.
loadstatement or selectstatement must result in a two-column table, where the first field contains the lower limit of each interval and the second field contains the upper limit of each interval. The intervals are always closed, i.e. the end points are included in the interval. Non-numeric limits render the interval to be disregarded (undefined) while NULL limits extend the interval indefinitely
I think following attached file help to understand the concept..
As i describe in a table there is 5 rows which is all ready loaded on to the qlikview application, then the 6 row as i mention which is added on the table. Then i again load this table on the Qlikview application but this time there is 6 rows is added on the table so i does not want to load the previousley loaded 5 rows because they are all ready loaded on the qlikview application.
So with the concept of the Interval Match i want to load only 6 row because it is newly added like wise suppose there is 1000 rows but newly added is 15 rows so total rows are 1015 but i want to load only newly added 15 rows how i can do this with the help of Interval match.