ESRI Shapefiles (SHP)¶
Also known as ESRI ArcView Shapefiles or ESRI Shapefiles. ESRI is the company that introduced this format. ArcView was the first product to use shapefiles.
Shapefiles are made up of a minimum of three similarly named files, with different suffixes:
Countries_area.dbf Countries_area.shp Countries_area.shx
Data Access / Connection Method¶
Shapefile access is built directly into MapServer. It is also available through OGR, but direct access without OGR is recommended and discussed here. The path to the shapefile is required. No file extension should be specified. Shapefiles only hold one layer of data, therefore no distinction needs to be made.
- The directory can serve as a data source.
- Each shapefile in a directory serves as a layer.
- A shapefile can also be a data source. In this case the layer has the same prefix as the shapefile.
Using ogrinfo on a directory with multiple shapefiles:
> ogrinfo /data/shapefiles/ INFO: Open of `/data/shapefiles/' using driver `ESRI Shapefile' successful. 1: wpg_h2o (Line String) 2: wpg_roads (Line String) 3: wpg_roads_dis (Line String) 4: wpgrestaurants (Point)
Using ogrinfo on a single shapefile:
> ogrinfo /data/shapefiles/Countries_area.shp Had to open data source read-only. INFO: Open of `Countries_area.shp' using driver `ESRI Shapefile' successful. 1: Countries_area (Polygon)
Using ogrinfo to examine the structure of the file/layer:
> ogrinfo -summary /data/shapefiles/Countries_area.shp Countries_area Had to open data source read-only. INFO: Open of `Countries_area.shp' using driver `ESRI Shapefile' successful. Layer name: Countries_area Geometry: Polygon Feature Count: 27458 Extent: (-180.000000, -90.000000) - (180.000000, 83.627419) Layer SRS WKT: (unknown) FAC_ID: Integer (5.0) TILE: Integer (3.0) ARCLIST: String (254.0) NAM: String (77.0) PERIMETER: Real (22.17) POLYGONCOU: Integer (6.0) NA2DESC: String (45.0)
Map File Example:
LAYER NAME my_shapefile TYPE POLYGON DATA countries_area STATUS OFF CLASS NAME "Countries" OUTLINECOLOR 0 0 0 END END