Mapping - ObjectVision/GeoDMS GitHub Wiki

Relational functions mapping

• mapping(SrcUnit, DstUnit)

mapping(SrcUnit, DstUnit) results in a relation with the index numbers of the domain unit DstUnit. The resulting attribute has as values unit DstUnit and as domain unit SrcUnit.

mapping(SrcUnit, DstUnit) is equivalent with convert(id (SrcUnit), DstUnit), but requires less memory.

• SrcUnit, DstUnit units with value types of the group CanBeDomainUnit

7.119

unit<uint32> RegionSrc: nrofrows = 5;
unit<uint32> RegionDst: nrofrows = 5;
attribute<Region> RegionDst_rel (RegionSrc) := mapping(RegionSrc, RegionDst);

domain RegionSrc, nr of rows = 5

• mapping_count