Feature property uploads as null- Google Earth Engine

Question

I am attempting to upload a feature collection which has a SURVEYDATE column. However, when I ask for the property, it returns null.

var table = ee.FeatureCollection("users/shopvac18/zm/NAS_ZM_2")

print(table.first())

// ee.Feature with a series of properties, including "SURVEYDATE"


print(ee.Feature(table.first()).get("SURVEYDATE"))

// null

Here is a link to a small example

Link to the original csv.

Answer 1

The property name seems to have a U+FEFF "Byte Order Mark" at the beginning of it, which is an invisible character some programs insert at the beginning of files (even though it really only means anything for the now-rare case of UTF-16 encoded text). Earth Engine does not strip this character, so the property name of the first column is not what it looks like and doesn't match.

You can access the property by writing the special character (escaped) as table.first().get("\uFEFFSURVEYDATE"), but it would be best to change whatever processing step inserted that character to not do so. However, I downloaded and examined your CSV file and it doesn't have the character in it. Are you sure that it's the exact same file that you used? I don't have a full explanation, given that.

Answer 2

Issue is probably due to inappropriate upload of CSV file to your assets. In following image of your table, it can be observed there are not coordinates for whatever feature.

In my case, however, where I uploaded original CSV to my assets, it looks as follows. Coordinates for each feature are present.

So, additionally to your code lines, I created a function for printing all 374 values for SURVEYDATE property (full code here).

var table = ee.FeatureCollection("users/joseguerreroa/NAS_ZM");

print(table.first());

print(ee.Feature(table.first()).get("SURVEYDATE"));

var getProperty = table.toList(table.size()).map(function (ele) {
  
  return ee.Feature(ele).get("SURVEYDATE");
  
});

print("SURVEYDATE", getProperty);

Result after running above code it can be observed in following image.