sortshp - sort a Shape data set
[ infile outfile item [ascending | descending] | -v]
sortshp sorts a Shape data set based on a single column in ascending or descending order. Supports INTEGER, DOUBLE and STRING column types. Useful for prioritizing shapes for rendering and/or labeling.
The idea here is that if you know that you need to display a certain attribute classed by a certain value, it will be faster for MapServer to access that value if it is at the beginning of the attribute file.
This example uses a roads file ('roads_ugl') that has a field with road classes in integer format ('class1').
sortshp roads_ugl roads-sort class1 ascending
Figure 1: Attributes Before sortshp
Figure 2: Attributes After sortshp
|18 September 2022|