In an auto-generated dimension, you don't have direct access to and, hence, can't manually rank, the dimension values. Instead, you must set a default rank order.
Default dimension value ranking is used with dimensions that are auto-generated.
To set a default dimension value rank order:
To better understand the difference between the dimension value ordering types, consider an example of a dimension called Score that has the dimension values 1, 5, 5.5, 9, and 10. The following table shows what the ordering would be for each type.
Original dimension | Alpha ordering | Integer ordering | Floating point ordering |
---|---|---|---|
-- Score |
1 |
1 |
1 |
-- 1 |
10 |
5 |
5 |
-- 5 |
5 |
5 |
5.5 |
-- 5.5 |
5.5 |
9 |
9 |
-- 9 |
9 |
10 |
10 |
-- 10 |
With integer ordering, the value 5.5 has been truncated to 5, and it is unclear which 5 is the original version and which is the truncated version. For some applications this may be acceptable, for others it is not. Additionally, integer ordering is significantly faster than floating point ordering. When choosing a numeric ordering type, you must balance the needs of your application against the extra time it takes to use floating point ordering.