For those not on 12cR1, or even perhaps if you are, the following two requirements came about at a customer site recently. Aggregate Append At that site (running 11gR2), there arose a need to aggregate all the islands of Australia into a single multi-polygon sdo_geometry. The first approach was to use SDO_AGGR_UNION (the customer isRead More
Someone downloaded my Spatial Companion for Oracle (SC4O) package the other day, then asked asked the following question(s): I have to calculate the intersection between two regions on a map. Each region is represented in the db as a >column in different tables. For now I have two columns of polygons one with 1500 entriesRead More
Oracle’s SDO_AGGR_UNION has always had horrible performance where the set of geometry objects to be unioned is somewhat more than trivial. (Trivial is not a well defined scientific term – experienced users of Oracle Spatial know what I am interfering.) The Oracle Spatial team were not unaware of the problems with their aggregate function. ToRead More