Spatial data mining algorithms heavily depend on the efficient processing o
f neighborhood relations since the neighbors of many objects have to be inv
estigated in a single run of a typical algorithm. Therefore, providing gene
ral concepts for neighborhood relations as well as an efficient implementat
ion of these concepts will allow a tight integration of spatial data mining
algorithms with a spatial database management system. This will speed up b
oth, the development and the execution of spatial data mining algorithms. I
n this paper, we define neighborhood graphs and paths and a small set of da
tabase primitives for their manipulation. We show that typical spatial data
mining algorithms are well supported by the proposed basic operations. For
finding significant spatial patterns, only certain classes of paths "leadi
ng away" from a starting object are relevant. We discuss filters allowing o
nly such neighborhood paths which will significantly reduce the search spac
e for spatial data mining algorithms. Furthermore, we introduce neighborhoo
d indices to speed up the processing of our database primitives. We impleme
nted the database primitives on top of a commercial spatial database manage
ment system. The effectiveness and efficiency of the proposed approach was
evaluated by using an analytical cost model and an extensive experimental s
tudy on a geographic database.