[Bug]: incorrect order when using `sort` with nouveau on multiple shards

Closed

#6,124 opened on Sep 22, 2026 1 comment 0 reactions 0 assignees View on GitHub

Nobody has claimed this yet.

Assessment

Difficulty: 4/5
Estimated time: 3-5 days
Newbie friendliness: 45/100

Issue type: Bug
Clarity: Clearly specified
Activity status: Active
Tech stack: erlang, python
Domain: databases, search

Research direction

The issue is in the Nouveau search module when sorting string fields across shards. Start by examining the Python reproducer script to understand the test setup. Look at the CouchDB source code for the Nouveau search implementation, focusing on sorting logic and shard merging. Running the reproducer against a local CouchDB instance will verify the bug. 'Done' means the sort order is correct across shards in the test.

Written by the indexing model from the issue text.

Description

bug needs-triage

Version

3.5.2

Describe the problem you're encountering

Dear CouchDB team,

It seems that there is a doc ordering issue in the following context:

using Nouveau search
with sort on a string field
with matching documents located on different shards

You can then end up with results such as ["apple", "Zebra", "apple"]

Expected Behaviour

I would expect sorting to work for documents across shards.

Steps to Reproduce

Here is a minimal reproducer, created by @AlexanderKaraberov
nouveau_min_repro.py

Your Environment

I was able to reproduce the issue on CouchDB 3.5.0 and 3.5.2. It can be reproduced with the docker image apache/couchdb:3.5.0.

Additional Context

No response

Dominant language: Erlang
Stars: 7k
Forks: 1.1k
Avg merge: 5h 24m
Merged PRs (30d): 10

Contributor guide

Open the contributing guide

First steps

Read the whole issue, then the project's contributing guide.
Comment on the issue to say you are picking it up — it saves two people doing the same work.
Fork the repository and make your change on a branch.
Open a pull request that references the issue number.

Similar issues

[BUG] CREATE property value with *, -, ^, % or unary minus is stored as its text ('2 * 3'); + and / are evaluated Open

bug

Difficulty 2/5 1-3 hours Newbie friendliness 75/100

orneryd/NornicDB#656 · Opened Sep 24, 2026
Statement leaks when a query fails to prepare, breaking `dbDisconnect()` Open

Difficulty 2/5 1-3 hours Newbie friendliness 75/100

r-dbi/adbi#73 · Opened Sep 24, 2026
[bug] GET /api/admin/audit-log forwards an unbounded `limit` to SQL LIMIT: ?limit=-1 dumps the whole audit table Open

Difficulty 2/5 1-3 hours Newbie friendliness 75/100

TencentCloud/Octop#1128 · 1 comment · Opened Sep 24, 2026
[bug][accuracy] Quebec basic personal amount is a year stale for every year (2024 holds the 2023 figure 17,183), which under-indexes the 2026+ Quebec IMR exemption Open

Difficulty 2/5 1-3 hours Newbie friendliness 75/100

elecnix/lifedraft#347 · Opened Sep 24, 2026
trace_query_origin makes DBConnector::isQueryType() classify every statement as non-mutable (replica routing sends writes to replicas, previewwrite executes writes) Open

Difficulty 2/5 1-3 hours Newbie friendliness 70/100

silverstripe/silverstripe-framework#12022 · 2 comments · Opened Sep 24, 2026

More Databases issues