Split Oracle Sdo_Geometry Linestring at a Known Point using PL/SQL (1)
This article describes how to split a linestring or a multilinestring using PL/SQL at a known point.
Oracle Spatial
Silence is Golden?
UPDATE The book has been published If any of my readers are wondering why I have been so quiet of late, here are the reasons. GeoRaptor Firstly I have been working on a new GeoRaptor release. That release was made a few weeks ago (12th February 2013). A lot of time and effort went intoRead More
Drawing a layer in GeoRaptor: Simple Gotchas!
A question from a user: It seems as though the system calculates extents that are HUGELY larger than the actual geometry. I have found by putting a label on it that you sill see a tiny blob then using the windowed zoom I can then start showing the links and eventual remove the label. Idea’sRead More
Spatial and Oracle 12c
Oracle 12c must be at least 6 months away. Here is a posting by spatialPhil on what may be in 12c for spatial practitioners. The real news in this posting is: Oracle Locator ‘beefed’ up The entire SDO_GEOM package will now be available in Locator (rather than previously where some of the more powerful functionsRead More
Changing Oracle Spatial Index Parameters on existing index
I received a question from a respected colleague: Can the parameters of a spatial index be altered? I created several dozen spatial indexes with a layer_gtype of polygon, I now have a requirement to modify them to be multipolygon…. My colleague wishes to do this without dropping the existing index. The answer to this isRead More
Writing Excel Spreadsheets files from within the Oracle database using Java and PL/SQL
My EXPORTER package + Java code has functions called WriteExcelSpreadsheet that can be used to create and export any SQL SELECT statement to disk as an Excel Spreadsheet using Oracle database’s DBMS_JOB or DBMS_SCHEDULER. Because Excel Spreadsheets have limited number of rows (65535) and columns (255) per sheet (the maximum size of data in aRead More
Writing xSV (eg csv) files from within the Oracle database using Java and PL/SQL
My EXPORTER package + Java code has a function called WriteDelimitedTextfile that can be used to export any SQL SELECT statement to disk using Oracle database’s DBMS_JOB or DBMS_SCHEDULER. Yes, you can export to disk via pure PL/SQL but I have added this function to my EXPORTER to create an integrated solution for exports thatRead More
A simple spike finder for Spatial
This is an old article that uses older custom code e.g. Vector2Geom(). Because the principles in the code are correct, I will bring the code up to date if anyone shows any interest. When investigating geometric or topological errors for linear or polygonal geometry objects, a range of tools are needed. Oracle has basic toolsRead More
JTS Java class compilation for 11g and above
Java classes loaded into the Oracle JVM are interpreted when executed up to and including Oracle 10gR2. For Oracle 11g and upwards, these loaded Java classes can be compiled to native code. I have added the optional compilation of my JTS Java wrappers and the source JTS classes to the JTS installer. The installation isRead More
Random Spatial Search Procedure
I have had the need, over the years, to produce statistics that helped me decide how effective a change to a property of a spatial table or index might be. Back in the old days of the Quad Tree index, I used a procedure like the following, to work out the best properties for aRead More