fix: Remote Online Store Type Inference Error with All-NULL Columns by yuan1j · Pull Request #6063 · feast-dev/feast

yuan1j · 2026-03-04T15:30:04Z

What this PR does / why we need it

📋 Problem Description

When reading features from a Feast Remote Online Store, a TypeError is raised if an entire feature column contains only NULL/NaN values. The error occurs in the python_values_to_proto_values() function when it cannot infer the value type from empty data.

🔍 Root Cause Analysis

Component	Issue
Location	`feast/type_map.py` - `python_values_to_proto_values()` function
Trigger	Entire feature column contains `NULL/NaN` values
Reason	Type inference fails when all values are empty, resulting in `UNKNOWN` value type
Current Behavior	Raises `TypeError: Couldn't infer value type from empty value`
Impact	Remote online feature reading fails completely

📊 Test Data Example

                   event_timestamp          driver_id  conv_rate  acc_rate  avg_daily_trips
0  2026-03-04 16:17:44+00:00       1001        NaN    1.000000           1000.0
1  2026-02-17 16:00:00+00:00       1005        NaN    0.708060            395.0
2  2026-02-17 17:00:00+00:00       1005        NaN    0.451616            145.0

⚠️ Note: The conv_rate column contains all NaN values.

💡 Solution

Modify the type inference logic to handle UNKNOWN value types gracefully:

Key Changes

✅ Do not raise error when value type is UNKNOWN
✅ Preserve schema-defined type from FeatureView definition
✅ Return proper NULL values in the response while maintaining type information

Code Change Summary

# Before
if value_type is UNKNOWN:
    raise TypeError("Couldn't infer value type from empty value")

# After
# Remove this part code, and use schema-defined type or skip type inference for NULL-only columns

✨ Expected Behavior

After this fix:

✅ Remote online store can read columns with all-NULL values
✅ Feature schema type is preserved from FeatureView definition
✅ NULL values are returned correctly to the client
✅ No breaking changes to existing functionality

Which issue(s) this PR fixes

Fixes: Remote Online Store Type Inference Error with All-NULL Columns

Related Error:

 Traceback (most recent call last):
  File "C:\svn\project\feature_store\feast\remote\test_workflow.py", line 130, in <module>
    run_demo()
  File "C:\svn\project\feature_store\feast\remote\test_workflow.py", line 25, in run_demo
    fetch_online_features(store)
  File "C:\svn\project\feature_store\feast\remote\test_workflow.py", line 121, in fetch_online_features
    returned_features = store.get_online_features(
  File "C:\Users\j\AppData\Local\Programs\Python\Python310\lib\site-packages\feast\feature_store.py", line 2445, in get_online_features
    response = provider.get_online_features(
  File "C:\Users\j\AppData\Local\Programs\Python\Python310\lib\site-packages\feast\infra\passthrough_provider.py", line 251, in get_online_features
    return self.online_store.get_online_features(
  File "C:\Users\j\AppData\Local\Programs\Python\Python310\lib\site-packages\feast\infra\online_stores\online_store.py", line 199, in get_online_features
    read_rows = self.online_read(
  File "C:\Users\j\AppData\Local\Programs\Python\Python310\lib\site-packages\feast\infra\online_stores\remote.py", line 169, in online_read
    message = python_values_to_proto_values(
  File "C:\Users\j\AppData\Local\Programs\Python\Python310\lib\site-packages\feast\type_map.py", line 838, in python_values_to_proto_values
    raise TypeError("Couldn't infer value type from empty value")
TypeError: Couldn't infer value type from empty value

Misc

🧪 Testing

Manual Test Steps

# 1. Start Feast services
cd C:\svn\project\feature_store\feast\test\feature_repo
feast ui
feast serve_registry
feast serve_offline
feast serve

# 2. Prepare test data with all-NULL column
# (conv_rate column contains only NaN values)

# 3. Run remote client
python remote/test_workflow.py

Configuration Used

project: test
registry: 
  registry_type: remote
  path: 127.0.0.1:6570
provider: local
online_store:
  type: remote
  path: http://127.0.0.1:6566
offline_store:
  type: remote
  host: 127.0.0.1
  port: 8815
entity_key_serialization_version: 3
auth:
  type: no_auth

📝 Additional Notes

Item	Details
Breaking Changes	None
API Changes	None
Documentation	May need update for NULL handling behavior
Unit Tests	Should add test case for all-NULL column scenario
Affected Components	`feast/type_map.py`, `feast/infra/online_stores/remote.py`

👥 Reviewers

@feast-maintainers
@feast-infra-team

✅ Checklist

Code follows Feast code conventions
Unit tests added/updated
Integration tests pass
Documentation updated (if needed)
Commits signed
PR title follows conventional commits format

yuan1j · 2026-03-04T15:33:36Z

小军已收到

yuan1j

Thank you for your helpful advice. This solution works for my case as well. Could you please review and approve the merge?

yuan1j · 2026-04-02T04:56:32Z

小军已收到

Signed-off-by: yuanjun220 <[email protected]>

…_columns

yuan1j · 2026-04-12T12:15:14Z

How can I merge these changes into the master branch?

…east-dev#6063) fix_remote_online_type_error_with_all_null_columns Signed-off-by: yuanjun220 <[email protected]> Signed-off-by: Alex Korbonits <[email protected]>

# [0.63.0](v0.62.0...v0.63.0) (2026-05-04) ### Bug Fixes * Add project filter to apply_data_source and delete_data_source (closes [#6206](#6206)) ([#6322](#6322)) ([96562c4](96562c4)) * Add project_id filter to SnowflakeRegistry UPDATE path ([#6243](#6243)) ([6658b71](6658b71)), closes [#6208](#6208) [#6208](#6208) * Add subprocess timeouts to prevent test_e2e_local hanging on Dask atexit handler ([3de6556](3de6556)) * Ambiguous truth value of array during materialization ([#6259](#6259)) ([d0c8984](d0c8984)) * Auto-detect GCS/S3 registry store when registry is passed as string ([#6260](#6260)) ([7ebcf03](7ebcf03)) * **bigquery:** Prefer query over table in get_table_query_string ([#6360](#6360)) ([77ed779](77ed779)), closes [#6200](#6200) * correct project_id scoping in get_user_metadata and delete_project ([0c469a7](0c469a7)) * disable Redis RDB persistence in test deployments ([44cd682](44cd682)) * Disable snowflake tests temporarily in CI ([#6356](#6356)) ([31d5a98](31d5a98)) * Filter empty SQL commands at execute_snowflake_statement call sites ([#6249](#6249)) ([92ffbb9](92ffbb9)) * Fix five bugs in milvus online store ([#6275](#6275)) ([212504b](212504b)) * Fix issue with apply feature view ([835cda8](835cda8)) * Fix streaming materialization for exotic sources with lazy UDF pipelines ([c07972d](c07972d)) * Handle missing features gracefully instead of panicking ([7d00b3a](7d00b3a)) * Harden informer cache with label selectors and memory optimizations ([#6242](#6242)) ([3f11356](3f11356)) * **helm:** Avoid nil pointer for metrics.enabled inside podAnnotations ([#6251](#6251)) ([c833f1a](c833f1a)) * Include git in feast server image ([fb03c46](fb03c46)) * Include StreamFeatureView in freshness metric ([#6269](#6269)) ([463f16c](463f16c)) * Pre-create S3A event log dir before SparkContext init ([#6317](#6317)) ([9feca77](9feca77)) * Remote Online Store Type Inference Error with All-NULL Columns ([#6063](#6063)) ([de67bdd](de67bdd)) * Remove selector with kustomize overlay using a JSON 6902 patch ([9107a43](9107a43)) * Resolve multiple bugs in SnowflakeRegistry and Snowflake connection handling ([#6315](#6315)) ([7e66a2e](7e66a2e)) * **spark:** BatchFeatureView with TransformationMode.PYTHON now reads all source columns ([a310eaf](a310eaf)) * **spark:** Use SELECT * when feature_name_columns is empty in pull_all_from_table_or_query ([e1b1d2d](e1b1d2d)) * Support pandas mode in feature builder and fix dask column extraction ([863315e](863315e)) * support SQL string as entity_df in RemoteOfflineStore.get_historical_features ([c559889](c559889)) * Wrap LocalOutputNode return value in ArrowTableValue for consist… ([#6286](#6286)) ([a16cd55](a16cd55)) ### Features * Add agent skills and Cursor/Claude rules for Feast development ([312eea3](312eea3)) * Add feature view versioning support to FAISS online store ([b36acb7](b36acb7)) * Add feature view versioning support to Redis and DynamoDB online stores ([#6257](#6257)) ([edf25af](edf25af)), closes [#6164](#6164) [#6163](#6163) * Add optional 'org' in feature view ([#6288](#6288)) ([#6301](#6301)) ([608b105](608b105)) * Add RaySource, to_ray_dataset first-class method, docs, and tests ([1c98157](1c98157)) * Add TLS support for Go Feature Server ([#6229](#6229)) ([28a58d0](28a58d0)) * Add Vector Search support to MongoDBOnlineStore ([#6344](#6344)) ([c102738](c102738)) * Add versioning support to Milvus online store ([#6330](#6330)) ([3268ced](3268ced)) * Addresses performance issues in the Redis online store ([2e50da0](2e50da0)) * Allow to set gpu for ray ([5580ab4](5580ab4)) * Bump redis-py version cap from <5 to <8 ([#6339](#6339)) ([9538180](9538180)) * Expose feature_server, materialization, and openlineage configuration via FeatureStore CRD ([ec6ecfd](ec6ecfd)) * Make online_write_batch_size configurable in MaterializationConfig ([#6268](#6268)) ([d41becf](d41becf)) * Make udf optional if agg defined ([#5689](#5689)) ([#6328](#6328)) ([f630056](f630056)) * MongoDB offline store ([#6138](#6138)) ([8eebad7](8eebad7)) * Optional input_schema for ODFV ([#6308](#6308)) ([#6312](#6312)) ([f08b4e8](f08b4e8)) * Provision minimal TokenReview RBAC for OIDC auth and add SSL error logging in token parser ([#6240](#6240)) ([dca57e8](dca57e8)) * **spark:** Add compute-on-read support for BatchFeatureView in get_… ([#6357](#6357)) ([630d9f8](630d9f8))

yuan1j requested a review from a team as a code owner March 4, 2026 15:30

This comment was marked as resolved.

Sign in to view

yuan1j commented Mar 11, 2026

View reviewed changes

yuan1j force-pushed the fix_remote_online_type_error_with_all_null_columns branch from 9eb84cd to cdcbc6a Compare April 2, 2026 14:50

yuan1j requested review from a team and sudohainguyen as code owners April 2, 2026 14:50

yuan1j requested review from lokeshrangineni, nquinn408 and redhatHameed and removed request for a team April 2, 2026 14:50

yuan1j force-pushed the fix_remote_online_type_error_with_all_null_columns branch 2 times, most recently from 75cc31c to e859233 Compare April 2, 2026 15:10

yuan1j requested a review from jyejare April 2, 2026 15:28

jyejare approved these changes Apr 7, 2026

View reviewed changes

fix_remote_online_type_error_with_all_null_columns

ec4282c

Signed-off-by: yuanjun220 <[email protected]>

ntkathole force-pushed the fix_remote_online_type_error_with_all_null_columns branch from f45e8c0 to ec4282c Compare April 7, 2026 14:16

ntkathole added the ok-to-test label Apr 7, 2026

Merge branch 'master' into fix_remote_online_type_error_with_all_null…

5531d11

…_columns

ntkathole approved these changes Apr 12, 2026

View reviewed changes

ntkathole merged commit de67bdd into feast-dev:master Apr 12, 2026
27 checks passed

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

fix: Remote Online Store Type Inference Error with All-NULL Columns#6063

fix: Remote Online Store Type Inference Error with All-NULL Columns#6063
ntkathole merged 2 commits into
feast-dev:masterfrom
yuan1j:fix_remote_online_type_error_with_all_null_columns

yuan1j commented Mar 4, 2026 •

edited by devin-ai-integration Bot

Loading

Uh oh!

This comment was marked as resolved.

Uh oh!

yuan1j commented Mar 4, 2026 via email

Uh oh!

This comment was marked as resolved.

Uh oh!

yuan1j left a comment

Uh oh!

yuan1j commented Apr 2, 2026 via email

Uh oh!

yuan1j commented Apr 12, 2026

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

Conversation

yuan1j commented Mar 4, 2026 • edited by devin-ai-integration Bot Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

What this PR does / why we need it

📋 Problem Description

🔍 Root Cause Analysis

📊 Test Data Example

💡 Solution

Key Changes

Code Change Summary

✨ Expected Behavior

Which issue(s) this PR fixes

Misc

🧪 Testing

Manual Test Steps

Configuration Used

📝 Additional Notes

👥 Reviewers

✅ Checklist

Uh oh!

This comment was marked as resolved.

Uh oh!

yuan1j commented Mar 4, 2026 via email

Uh oh!

This comment was marked as resolved.

Uh oh!

yuan1j left a comment

Choose a reason for hiding this comment

Uh oh!

yuan1j commented Apr 2, 2026 via email

Uh oh!

yuan1j commented Apr 12, 2026

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

yuan1j commented Mar 4, 2026 •

edited by devin-ai-integration Bot

Loading