Dictionary issue
I have the following script and the issues I am having is that the PermitNum can have multiple Par (par field) numbers but my current script will only populate the Parel field with just one Par attribute, it doesn't transfer each parcel that corresponds with each permit number. How can I adjust my current code to transfer each parcel number?
fc_dest = "D:/Temp/Cases"
sourceFC = "D:/Temp/Casestableview"
#Use Dictionary to update fc fileds.
sourceFieldsList = ['PermitNum','Par','AppS','AppT', 'SubT','Desc', 'MainApp', 'PA', 'Status', 'AppStatus', 'DecDate',]#,'ProjectInfo', 'Contractor', 'Subdivision', 'TwnRngSec', 'LivingSpace', 'TotalSqFt', 'Value_', 'Valuation', 'Status']
# Use list comprehension to build a dictionary from a da SearchCursor
valueDict = {r[0]:(r[1:]) for r in arcpy.da.SearchCursor(sourceFC, sourceFieldsList)}
updateFieldsList = ['PermitNum','Par','AppS','AppT', 'SubT','Descr', 'MainApp', 'PA', 'Status', 'AppStatus', 'DecDate']
with arcpy.da.UpdateCursor(fc_dest, updateFieldsList) as updateRows:
for updateRow in updateRows:
# store the Join value of the row being updated in a keyValue variable
keyValue = updateRow[0]
# verify that the keyValue is in the Dictionary
if keyValue in valueDict:
# transfer the values stored under the keyValue from the dictionary to the updated fields.
for n in range (1,len(sourceFieldsList)):
updateRow[n] = valueDict[keyValue][n-1]
updateRows.updateRow(updateRow)
del valueDict
Base on the PermitNum, For example permit 2020-0014 has 7 records in the Par field in the table I need it to transfer the tables Par field records to the feature classes Par field if they don't exits in the feature class, 2020-0013 has 4 permit records in the table I need to only transfer the two Par records to the feature class since it already the feature class already has two populated. I don't need to transfer ones that already in the feature classes Par field. Hopefully this makes sense. I can attach some data if that would help?
Thank you for responding I am very appreciative.
It wont let me open the sample shapefile but it let me view the Permits_view so I built an example using its 3 fields. Same concept for the shapefile- you just have to find a combination of fields to create the 'key' in your dictionary. You can add more fields to the concatenation if needed/available until you get unique keys.
This is an image of the code at work so you can see the values in the dictionary:
valueDict = {}
with arcpy.da.SearchCursor(sourceFC, ['OBJECTID', 'PermitNum', 'Par']) as sCur:
for row in sCur:
# str(row[sCur.fields.index('AppS')]).replace('/', '') <- use this to convert the dates in the App fields to strings
concatenatedKey = row[sCur.fields.index('PermitNum')] + str(row[sCur.fields.index('Par')])
if concatenatedKey in valueDict.keys():
print(f'duplicate concatenation: {concatenatedKey}')
else:
valueDict[concatenatedKey] = row[sCur.fields.index('OBJECTID')]
Then once the 'source' dictionary is built, you concatenate the same fields in the target shapefile and use it to lookup the valuesDict.
with arcpy.da.UpdateCursor(sourceFC, ['OBJECTID', 'PermitNum', 'Par']) as uCur:
for row in uCur:
if row[2] is None:
lookupKey = row[sCur.fields.index('PermitNum')] + str(row[sCur.fields.index('Par')])
if lookupKey in valueDict.keys():
print(f'{lookupKey} found, setting Par to: {valueDict.get(lookupKey)}')
uCur.updateRow(row)