topic Re: Feature size increasing after truncate and append in ArcGIS API for Python Questions

Feature size increasing after truncate and append

twangtx — Thu, 12 Feb 2026 22:28:22 GMT

Hi Everybody,

I've encountered some inexplicable result when I'm running daily/weekly python scripts to updated hosted feature layers in ArcGIS Online where the feature storage size seems to balloon in size after each truncate and append option. The hosted feature layer started a few weeks ago at like 60mb of feature storage, but it's now 1.5gbs and I'm at a loss at what's happening.

The layer is sync and edit enabled.

Basically we have two methods of updating feature layers.

1. Is where we call rest endpoint directly and perform arcpy delate rows and append. And it seems to work and the end user doesn't seem to notice any issues.

HFL URL = "[URL]"
arcpy.DeleteRows_management(HFL URL)
arcpy.Append_management(Local FC Source, HFL URL,"NO_TEST")

2. The other method, we zip up a file geodatabase, upload it to AGO and perform a truncate and append (from the fgdb) to the feature layer.

Below are the steps after the zipped fgdb gets uploaded to AGO.

flc.manager.update_definition({"capabilities": "Create,Delete,Query,Update,Editing,Sync", "syncEnabled": False})
featLyr.manager.truncate()
flc.manager.update_definition({"capabilities": "Create,Delete,Query,Update,Editing,Sync", "syncEnabled": True})
featLyr.append(item_id=fgd_item.id,
  upload_format="filegdb",
  upsert=False,
  field_mappings=[])

We also have scripts that just item.publish(overwrite=True), but it's a little more finicky I've found to use than the truncate and append, until now. But I've not noticed feature layers exploding in storage space.

I almost feel like there should be like there's an adds and deletes table that needs to be compressed or something in AGO.

Has anyone encountered this issue or have any insights?

Thank you,

Thomas

Re: Feature size increasing after truncate and append

AaronKoelker — Fri, 06 Mar 2026 16:50:02 GMT

I know you're disabling it mid-step, but can you test it with a duplicate feature layer that doesn't have sync enabled at all? Sounds like it is still storing previous versions or a history of previous edits somewhere, and if you're doing a full truncate/append that's a lot of "edits".

When I need to do full overwrites I either use the .update() method to replace the whole file, or use spatially enabled dataframes (SEDF) and .edit_features(adds='your SEDF'). Something like the examples below. Could try one of these as an alternative to append() .

### Update Hosted Feature Layers Examples from arcgis.gis import GIS from arcgis.features import FeatureLayerCollection updated_data = r'this_is_a_path_to_file.csv' # path to your updated dataset, the file type must match whatever the service was published with itemid = '' # the itemid for the hosted feature service you want to update in ArcGIS Online, you can get it off item page in AGO portal_url = '' # "https://example.maps.arcgis.com" user = '' # AGO username pw = '' # AGO password ### Log in to ArcGIS Online account gis = GIS(portal_url, user, pw) un = gis.properties.user.username print(f'\nLogged in as {un} on {portal_url} \n') ############################################################################# ### Example 1 (Overwrite directly from local file) # If you published to AGO from a local file (csv, fgdb, etc.), this is the simplest way to overwrite # The new data must have the same filename and file type, and FGDBs must be zipped hostedfeature = gis.content.get(itemid) flayer = FeatureLayerCollection.fromitem(hostedfeature) flayer.manager.overwrite(updated_data) print("Hosted feature layer updated with the latest and greatest") # That is the barebones method, but you can update lots of other stuff too, for example the description, title, etc. # https://developers.arcgis.com/rest/users-groups-and-items/common-parameters/ item_properties={ "description":"Here is my description, isn't it great", "title":"Great Item Title" } hostedfeature.update(item_properties) # Or the thumbnail thumb = r'path_to_some_picture.jpg' # can also use a image url hostedfeature.update(thumbnail=thumb) # Or you can disable and enable settings, like Sync syncoff = {"capabilities": "Query, Extract"} hostedfeature.manager.update_definition(syncoff) syncon = {"capabilities": "Query, Extract, Sync"} hostedfeature.manager.update_definition(syncon) # https://developers.arcgis.com/python/latest/samples/overwriting-feature-layers/#:~:text=updated_capitals_csv%27%2C%20csv_file_name))-,Overwrite%20the%20feature%20layer,-Let%20us%20overwrite ############################################################################# ### Example 2 (Go the edit route with a full truncate and append) # You can do this either from a regular pandas dataframe if it's a table, a spatially enabled dataframe if there is geometry, or from a featureset # If you are adding more than 1000 features you want to chunk it out import pandas as pd import os hostedfeature = gis.content.get(itemid).layers[0] # if you have a hosted table you can use .tables[0] instead hostedfeature.manager.truncate() local_featureclass = os.path.join(r"path to a file geodatabase .gdb", "MyFeatureClass") sedf = pd.DataFrame.spatial.from_featureclass(local_featureclass) n = 1000 for i in range(0, len(sedf), n): chunk = sedf[i:i+n] result = hostedfeature.edit_features(adds=chunk) print(f'added items {i+1}-{i+n}...')

Re: Feature size increasing after truncate and append

twangtx — Wed, 11 Mar 2026 15:49:01 GMT

Hi Aaron,

Thank you for responding.

I think we've got the issue "resolved" in that we kind of just went with the nuclear option. We ended up just overwriting the hosted feature layer from Pro with a feature class of the same schema. And the method that has been working for us so far is:

Zip up a file geodatabase
Upload to AGO
Disable sync
Truncate
Append from file geodatabase
Reenable sync
Delete the file geodatabase in AGO.

I think maybe the critical thing we did was append before reenabling the sync.

It's been running daily for a few weeks, and the feature storage size has been staying consistent.

Thank you,

Thomas

Re: Feature size increasing after truncate and append

AaronKoelker — Thu, 12 Mar 2026 18:42:50 GMT

Ah that makes sense, I didn't catch that in the original code you shared. Moving the reenable sync step to after the append was almost certainly it. Glad you were able to figure it out.