O'Reilly logo

Applying and Extending Oracle Spatial by Siva Ravada, Simon Gerard Greener

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

Creating spatial autocorrelation via clustering

When spatial data is loaded into a table, data is usually organized depending on the order of the incoming rows. This ordering of the data on disk has a direct impact on the performance of the spatial queries. Consider a simple SDO_ANYINTERACT query that retrieves all the data inside a rectangular box. After the spatial query is performed, the rows that satisfy the result are retrieved from the table. If all of these rows are spread over different data blocks, the cost of the query increases, as many blocks have to be fetched to form the result set. If data in the blocks can be organized in such a way to minimize the number of blocks fetched for each query, the query performance would improve. This ...

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required