For along time, shapefile has being my primary GIS file for working with vector data. I have never had any reason to look beyond shapefile for handling my GIS vector datasets not until recently when I have a need to store some large quantity of text string in the attribute table.
Before I share my story, let make a point to what a shapefile is just in case you don't know it.
Shapefile is a file type developed by ESRI to handle vector map data in the form of points, polylines and polygons. More details can be found on the Wikipedia page as summarized in the picture below, also on the 'Shapefile Technical Description' document.
Limitations of a Shapefile
Specifically, I was trying to convert a KML file to shapefile. Then one of the columns that had alot of text/string content gets truncated when converted to shapefile. I couldn't figure out why and what caused that until I found this website (Switch from Shapefile) that listed listed some its limitations and that one that affected my situation directly was that the maximum characters is 254.
No way! My attribute table has way more than 254 characters. Then I had to look beyond a shapefile. I actually settled with a GeoJSON file type.
Once again as listed on the website Switch from Shapefile, other limitations include:-
~ No coordinate reference system definition.
~ It's a multifile format.
~ Attribute names are limited to 10 characters.
~ Only 255 attributes. The DBF file does not allow you to store more then 255 attribute fields.
~ Limited data types. Data types are limited to float, integer, date and text with a maximum 254 characters.
~ Unknown character set. There is no way to specify the character set used in the database.
~ It's limited to 2GB of file size. Although some tools are able to surpass this limit, they can never exceed 4GB of data.
~ No topology in the data. There is no way to describe topological relations in the format.
~ Single geometry type per file. There is no way to save mixed geometry features.
~ More complicated data structures are impossible to save. It's a "flat table" format.
~ There is no way to store 3D data with textures or appearances such as material definitions. There is also no way to store solids or parametric objects.
~ Projections definition. They are incompatible or missing.
~ Line and polygon geometry type, single or multipart, cannot be reliably determined at the layer level, it must be determined at the individual feature level.
Now you know some troubles you may encounter with you shapefile data are due to some of these limitations, so no need to full your hair just switch to a more advanced GIS file type.
Before I share my story, let make a point to what a shapefile is just in case you don't know it.
Shapefile is a file type developed by ESRI to handle vector map data in the form of points, polylines and polygons. More details can be found on the Wikipedia page as summarized in the picture below, also on the 'Shapefile Technical Description' document.
Limitations of a Shapefile
Specifically, I was trying to convert a KML file to shapefile. Then one of the columns that had alot of text/string content gets truncated when converted to shapefile. I couldn't figure out why and what caused that until I found this website (Switch from Shapefile) that listed listed some its limitations and that one that affected my situation directly was that the maximum characters is 254.
No way! My attribute table has way more than 254 characters. Then I had to look beyond a shapefile. I actually settled with a GeoJSON file type.
Once again as listed on the website Switch from Shapefile, other limitations include:-
~ No coordinate reference system definition.
~ It's a multifile format.
~ Attribute names are limited to 10 characters.
~ Only 255 attributes. The DBF file does not allow you to store more then 255 attribute fields.
~ Limited data types. Data types are limited to float, integer, date and text with a maximum 254 characters.
~ Unknown character set. There is no way to specify the character set used in the database.
~ It's limited to 2GB of file size. Although some tools are able to surpass this limit, they can never exceed 4GB of data.
~ No topology in the data. There is no way to describe topological relations in the format.
~ Single geometry type per file. There is no way to save mixed geometry features.
~ More complicated data structures are impossible to save. It's a "flat table" format.
~ There is no way to store 3D data with textures or appearances such as material definitions. There is also no way to store solids or parametric objects.
~ Projections definition. They are incompatible or missing.
~ Line and polygon geometry type, single or multipart, cannot be reliably determined at the layer level, it must be determined at the individual feature level.
Now you know some troubles you may encounter with you shapefile data are due to some of these limitations, so no need to full your hair just switch to a more advanced GIS file type.
