How to copy new rows from a shapefile to a feature class

Question

Hi, I am trying to add new features from a shapefile to a feature class sitting in database in sql server. Both have common fields but name of a few fields are different. My question is that how can I automate this process using a python script. I am new with Python and I've created this one but I am getting this error: Runtime error Traceback (most recent call last): File "", line 16, in File "", line 4, in getPrimaryFieldValues TypeError: 'field_names' must be string or non empty sequence of strings. My script looks like this: ID is the field that the script should check it if the values don't exist then insert the rows. import arcpydef getPrimaryFieldValues(fc, field😞 values = [] with arcpy.da.SearchCursor(fc, [field]) as cursor: for row in cursor: values.append(row[0]) return valuesdef getSelectCursor(fc, whereClause😞 return arcpy.da.SearchCursor(fc, ["*"], whereClause)def diff(a, b😞 b = set(b) return [aa for aa in a if aa not in b]source = r"original"destination = r"test"fieldName =["ID"]sourceValues = getPrimaryFieldValues(source, fieldName)destinationValues = getPrimaryFieldValues(destination, fieldName)add = diff(sourceValues,destinationValues)with arcpy.da.InsertCursor(destination, ["*"]) as insertCursor: for a in add: insertRows = getSelectCursor(source, fieldName + " = " + str(a)) for r in insertRows: insertCursor.insertRow(r)

Anonymous User · Answer

Thanks for pasting the script.

In your updated code, the whereclause is missing.  Using the whereclause in the original pasting, it looks like you were trying to select the fieldname by the sql statement, which will fail because the whereclause is for filtering/selecting the data.

If you are only comparing the one (GeoUnit) field, you only need to grab that value in your lists.  I refractored your code a little to:

import arcpy

def diff(a, b):
    # Filter out existing values
    return [aa for aa in a if aa not in b]

if __name__ == "__main__":
    source = "Original"
    destination = "Test"
    fieldNameList = ['OBJECTID', 'F_1', 'F_2', 'Description', 'Class', 'CatShortDesc', 'CatLongDesc', 'Condition', 'GeoUnit', 'Easting', 'Northing', 'created_user', 'created_date', 'last_edited_date', 'SHAPE@XY', 'Comments', 'Class_Code']

additions = diff([x[0] for x in arcpy.da.SearchCursor(source, 'GeoUnit')],
                     [x[0] for x in arcpy.da.SearchCursor(destination, 'GeoUnit')])

# iterate over list of GeoUnit values that are not in the featureclass
    for a in additions:
        # select the values in the shapefile based on the whereclause
        whereclause = f"""GeoUnit = '{a}'"""
        with arcpy.da.SearchCursor(source, fieldNameList, whereclause) as cur:
            for row in cur:
                # Insert the values from the shapefile cursor into the fc.
                # The order of the fields in the fieldlist matters here so match their index to the index of the destination FC that you are using.
                with arcpy.da.InsertCursor(destination, fieldNameList) as insertCursor:
                    insertCursor.insertRow(row[0])

Hope this helps, and that I understood your intention.  You could do this with dictionaries as well, so you don't have to iterate over the shapefile a second time but this might work just as well without getting too complex.

MaryamPanji · Answer

Thanks Dan, I fixed the script.

MaryamPanji · Answer

import arcpy
def getPrimaryFieldValues(fc, field):
	values = []
	with arcpy.da.SearchCursor(fc, [field]) as cursor:
		for row in cursor:
			values.append(row[0])
	return values

def getSelectCursor(fc, whereClause):
	return arcpy.da.SearchCursor(fc, fieldName, whereClause)

def diff(a, b):
	b = set(b)
	return [aa for aa in a if aa not in b]

source = "Original"
destination = "Test"
fieldName = ['OBJECTID','F_1','F_2','Description','Class','CatShortDesc','CatLongDesc','Condition','GeoUnit','Easting','Northing','created_user','created_date','last_edited_date','SHAPE@XY','Comments','Class_Code']

sourceValues = getPrimaryFieldValues(source, fieldName)
destinationValues = getPrimaryFieldValues(destination, fieldName)

additions = diff(sourceValues,destinationValues)

with arcpy.da.InsertCursor(destination, fieldName) as insertCursor:
	for a in additions:
		insertRows = getSelectCursor(source, fieldName)
		for r in insertRows:
			insertCursor.insertRow(r)