Module 2: Working with different data sources

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Different data types

In GeoDMS you can read many different data types:

  • Tables: .csv, .asc, .dbf, .xml, .xdb, .txt
  • Grid raster: .tif, .asc
  • Vector: .shp
  • GeoDMS' own data storage file: .fss
  • Databases: MsAccess, PostgreSQL/PostGIS, FileGeoDatabase

In the following configuration file you'll see example of how you can configure several common data types: download configuration. How to set up this configuration see: Module 0: Install GeoDMS GUI and setup a configuration

Now you should navigate to SourceData and here you'll see serveral types of SourceData listed. Click on the top one called: "Raster_TifData", and press CTRL + E or right-click and choose "Edit Config Source". That will open a text editor, preferably Notepad++

unit<ipoint> Raster_TifData 
: StorageName = "%ProjDir%/Data/bbg2015_100m_10k.tif"
, StorageType     = "gdal.grid"
, StorageReadOnly = "true"
, DialogData = "rdc_base"
	attribute<uint8> grid (NL_grid/domain);

When reading source data, you load a data set of a certain domain. To define that domain in GeoDMS, configure a unit with several properties.

  • StorageName: this tells GeoDMS where to find the datafile
  • StorageType: what storage reader should be used. For external rasterfiles use "gdal.grid", for ESRI-shapefiles use "gdal.vect".
  • StorageReadOnly: specify whether GeoDMS is allowed to edit files.
  • DialogData: what attribute should be used to visualise the dataset.

By convention you should configure your configuration in a way that all data that is just being read should be in SourceData, and then when you do any analysis that should be done in the Analysis container. This way there is a natural division between the original data and the manipulated data/results.

The GeoDMS cannot check whether certain data types have been changed between sessions, i.e. shapefiles. Therefore, it recalculates everything that uses such data types. A way to circumvent this and thefefore speed up repeated calculation is to save such data type to GeoDMS' own data storage file (.fss). You have to do that once and then direct expressions towards that disconnected data attribute.

Go to previous module: Module 1: Learning the basic concepts of GeoDMS

Go to next module: Module 3: Doing basic analyses with vector data

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