Comparison of geodata formats: Difference between revisions
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=== Open formats === | === Open formats === | ||
Shapefile - A "shapefile" is really a collection of files with the same name but different extensions. | Shapefile - Pretty much "owned" by ESRI but everyone has adopted it. | ||
A "shapefile" is really a collection of files with the same name but different extensions. | |||
The projection (if it is defined) is stored in ''filename.prj''. This is an ASCII file. You can cheat and copy and rename it to define projection on other shapefiles; of course, this does not reproject data. Shapefiles created with ArcView 3.x do not have prj files. | The projection (if it is defined) is stored in ''filename.prj''. This is an ASCII file. You can cheat and copy and rename it to define projection on other shapefiles; of course, this does not reproject data. Shapefiles created with ArcView 3.x do not have prj files. | ||
Revision as of 21:34, 6 February 2018
I suppose you want an actual comparison, not just a list.
This is as far as I have gotten.
Ask me for it and I will write it. :-)
Brian Wilson 16:14, 15 January 2006 (PST)
ESRI proprietary formats
Coverage - ancient, dead format still widely in use by people clinging to the last remaining copies of ArcInfo. ESRI no longer provides any reasonable documentation. Good luck. See this Library of Congress doc: https://www.loc.gov/preservation/digital/formats/fdd/fdd000284.shtml
Personal Geodatabase - deprecated, based on obsolete 32-bit Microsoft technology
You can add an entire Feature Dataset to a ArcMap with drag-and-drop from ArcCatalog. I find this handy.
File Geodatabase - File based, still highly proprietary but accessible via an API that is free.
Layer file - When you save a layer file, the file filename.lyr is created for the layer to store symbology design and layout information, so that you can reuse those settings in other maps.
Open formats
Shapefile - Pretty much "owned" by ESRI but everyone has adopted it. A "shapefile" is really a collection of files with the same name but different extensions.
The projection (if it is defined) is stored in filename.prj. This is an ASCII file. You can cheat and copy and rename it to define projection on other shapefiles; of course, this does not reproject data. Shapefiles created with ArcView 3.x do not have prj files.
Tabular data for attributes is stored in a DB IV format file called filename.dbf
When ArcCatalog creates metadata for the file, it puts it in filename.xml.
Data interchange formats
ESRI ASCII (e00) format
