If you're working with 10.1 (my guess from the helpfile that you linked) and using the trick to bring in the nodes of the polygons and having Tableau draw them by connecting the dots, that is one gigantic file. I just downloaded the Texas school districts the Census, and it looks like you're trying to work with about 1.7 million vertices (and, at least on my computer when I exported the shapefile polygons to a CSV of vertices, 165MB on data). That's one big CSV. It shouldn't be too large to open in Tableau though. I can open the file without a problem in 10.0, but I haven't tried drawing it as polygons...because I forgot to add in an ordering attribute when I exported the CSV. It should work though.
Now, if you try to open the CSV in Excel, that very well may freak out. I don't remember what the maximum number of rows is...
You could try simplifying the polygons in a GIS before creating the nodes.csv. Or, if you could jump to Tableau 10.2 or later, the shapefile of school districts opens beautifully (and Tableau uses some smarts to optimize the geometry to speed things up)...no need to wrestle with all of the vertices.
Thank you so much. I have Tableau 10.4. In response to your sentence " if you could jump to Tableau 10.2 or later, the shapefile of school districts opens beautifully (and Tableau uses some smarts to optimize the geometry to speed things up)...no need to wrestle with all of the vertices" -- how do I do that exactly? I have only imported shapefiles using the method in the link I included. Do you mind walking me through it? Thank you so much. I appreciate your help. The other piece of this is that I usually edit the nodes and attributes files to add layers on top of my maps. If I am unable to oepn the nodes.csv file, how can I add new intformation (i.e. adding new latitude and longitudes?
Hi Alyssa -
Cool that you have 10.4! That should make things a lot easier. To add a shapefile without converting to vertices using QGIS and then connecting the dots you can just add the shapefile directly starting with version 10.2. Here is the official help file (Create Tableau Maps from Spatial Files). You can add directly by connecting to a spatial file:
Or, I normally just open up my file directory with the shapefile, grab the part of the file with the .shp extension and drop it into Tableau (see image below for the file that I grab from all of the parts that make a shapefile). Either way, it should give you a GEOMETRY Measure. Drop the GEOMETRY onto the viz and put any unique ID in the dataset on Detail to separate out the polygons for the school districts. The Census data should have a few different fields that you could use as unique identifiers.
As for editing to add layers on top of your maps. If you just need to add some points on top from a file with latitude and longitude, I'd suggest a dual axis map. I've written up a few ways to make dual axis maps so one of these here might help: Dual Axis Mapping - Many Ways