The simplest spatial properties of a feature which can be used in filter condition are:
Area;
Length.
Length property is applicable to area and raster features, and Area property is applicable to line, area and raster ones. In this case length of area and raster features is interpreted as their perimeter, i.e. total length of feature's outer boundary and all its inner boundaries. Length and area are calculated by the system based on the feature's coordinates.
As lengths and areas are numerical values, the comparison relations and relations of diapasons/intervals are allowed for them (see chapter 26 'Searching records in a table”, table 26-2 and table 26-3). For comparison relations one numerical argument is also required with which area or length will be compared, and for relations of diapasons/intervals two arguments are required.
Thus, Length and Area properties allow building simple condition of features filtration like these:
area of a building is greater than 100 m2;
length of a fence is not greater than 50 m;
perimeter of a parcel lies in the diapason from 500 to 700 m.
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