My good friend Regina Obe has taken my article Loading and Processing GPX 1.1 files using Oracle XMLDB and implemented it using PostgreSQL’s XML implementation. For those who are interested the article is called Loading and Processing GPX XML files using PostgreSQL
A colleague is trying to load shapefiles into SQL Server 2008 and asked me the following question: I’m migrating mapinfo and/or shapefiles GDA94 files into sql 2008 geography data type (SRID 4283). I’m using the free Shape2SQL or EasyLoader. Some files fall over with .net exceptions. I suspect something about the coordinates not being validRead More
Someone on the PostGIS discussion list asked about a problem converting an Oracle database to PostGIS and he had run into some difficulties with Oracle’s Optimized Rectangles. Is there a way to store rectangles in postGIS in a similar fashion? With the “similar fashion” being all about converting to equivalent 5 vertex POLYGONS: I understandRead More
Over at Alex Willmer’s Misspelled nemesis club there has been a (now-closed) discussion on the successor to the ubiquitous shapefile. Alex points out a lot of the benefits of the shapefile (and there certainly have been many). Before we discuss its “successor”, we should reflect on our business needs and the problems we had withRead More
I received an email a few weeks ago asking: I was wondering if you could post an article explaining how to create a polygon from overlapping lines, if this is possible. I am new as in 1 week into exploring this product and am finding the documentation for ST_BuildArea and the like a little hardRead More
There are a large number of geospatial data storage, delivery and interchange formats around nowadays. Including (I limit this discussion to vector data formats only): Geography Markup Language (GML) Keyhole Markup Language GPS eXchange Format (GPX) Vector Markup Language (VML) Scalable Vector Graphics (SVG) Victorian Government’s (Aust) Incremental Update Format (IUF) New South Wales Government’sRead More
I recently wrote an article on the use of External File with Oracle tables to load point data into Oracle. I thought I would have a look on how to do this in PostGIS. A bit of research came up with the PostgreSQL COPY SQL command. There appears to be no equivalent to Oracle’s OrganisationRead More
There have been many, many articles written on the web describing how to access external data (data held in operating system files not under the control of Oracle and not stored within its own datafiles and tablespaces) from within Oracle such that one can query the data using SQL. In short, Oracle allows a userRead More
Oracle makes available for download from its website a shapefile loader called shp2sdo. Loading data using this tool is a four step process: Execute shp2sdo to create a set of sqlplus and sqlldr files. Use SQLPlus to run the SQL file generated by shp2sdo to create the table and user_sdo_geom_metadata entries. Load the actual dataRead More
Yesterday, I posted a short article on Converting Google Earth Formatted Longitude/Latitude points to decimal degrees. The Google Earth longitude/latitude values are expressed as a string containing degree, minute and seconds values with text separators as follows: Latitude Longitude 43� 0�50.60�S 147�12�18.20�E The function described was written in PL/SQL for Oracle. Regina Obe emailed meRead More