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FA-45771 / Data systems / Open access

Exchange drops row identity while transferring payload · case 01

Exchange drops row identity while transferring payload.

Verified by executionVariant 1 · 7 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

partition-exchange-routing: Exchange drops row identity while transferring payload.

THE FAILURE

partition-exchange-routing: Exchange drops row identity while transferring payload.

Unsuccessful approach: Swapping identity and payload still changes the receiver schema.

Case contract

Route [id,key,payload] rows into fixed receiver partitions using a supplied key-to-partition table. Null keys use the explicit null partition; unmapped non-null keys produce UNMAPPED side output. Preserve source order within each receiver, retain empty receivers, and preserve repeated rows.

Why this case matters

A bounded deterministic data engine model makes representation and changelog faults reproducible.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(d):
    try:
        rows,mapping,null_partition,count=d
        receivers=[[] for _ in range(count)]; rejected=[]
        for ident,key,payload in rows:
            if key is None: target=null_partition
            elif str(key) in mapping: target=mapping[str(key)]
            else: rejected.append([ident,'UNMAPPED']); continue
            receivers[target].append([key,payload])
        return [receivers,rejected]
    except (IndexError, KeyError, ValueError, StopIteration) as exc:
        return {"representation_error": type(exc).__name__}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
if N == 1:
    check('independent receivers', solve([[[10, 1, 1], [11, 2, 2]], {'1': 0, '2': 1}, 1, 3]), [[[[10, 1]], [[11, 2]], []], []])
    check('null receiver', solve([[[10, None, 1]], {}, 1, 3]), [[[], [[10, 1]], []], []])
    check('unmapped', solve([[[10, 7, 1]], {'1': 0}, 1, 2]), [[[], []], [[10, 'UNMAPPED']]])
    check('same receiver order', solve([[[11, 1, 1], [10, 1, 2]], {'1': 0}, 1, 2]), [[[[11, 1], [10, 2]], []], []])
    check('duplicate rows', solve([[[10, 1, 1], [10, 1, 1]], {'1': 0}, 1, 2]), [[[[10, 1], [10, 1]], []], []])
    check('mapped zero', solve([[[10, 0, 1]], {'0': 1}, 0, 2]), [[[], [[10, 1]]], []])
    check('empty relation', solve([[], {}, 0, 2]), [[[], []], []])
elif N == 2:
    check('independent receivers', solve([[[10, 1, 2], [11, 2, 3]], {'1': 0, '2': 1}, 1, 3]), [[[[10, 2]], [[11, 3]], []], []])
    check('null receiver', solve([[[10, None, 2]], {}, 1, 3]), [[[], [[10, 2]], []], []])
    check('unmapped', solve([[[10, 7, 2]], {'1': 0}, 1, 2]), [[[], []], [[10, 'UNMAPPED']]])
    check('same receiver order', solve([[[11, 1, 2], [10, 1, 3]], {'1': 0}, 1, 2]), [[[[11, 2], [10, 3]], []], []])
    check('duplicate rows', solve([[[10, 1, 2], [10, 1, 2]], {'1': 0}, 1, 2]), [[[[10, 2], [10, 2]], []], []])
    check('mapped zero', solve([[[10, 0, 2]], {'0': 1}, 0, 2]), [[[], [[10, 2]]], []])
    check('empty relation', solve([[], {}, 0, 2]), [[[], []], []])
elif N == 3:
    check('independent receivers', solve([[[10, 1, 3], [11, 2, 4]], {'1': 0, '2': 1}, 1, 3]), [[[[10, 3]], [[11, 4]], []], []])
    check('null receiver', solve([[[10, None, 3]], {}, 1, 3]), [[[], [[10, 3]], []], []])
    check('unmapped', solve([[[10, 7, 3]], {'1': 0}, 1, 2]), [[[], []], [[10, 'UNMAPPED']]])
    check('same receiver order', solve([[[11, 1, 3], [10, 1, 4]], {'1': 0}, 1, 2]), [[[[11, 3], [10, 4]], []], []])
    check('duplicate rows', solve([[[10, 1, 3], [10, 1, 3]], {'1': 0}, 1, 2]), [[[[10, 3], [10, 3]], []], []])
    check('mapped zero', solve([[[10, 0, 3]], {'0': 1}, 0, 2]), [[[], [[10, 3]]], []])
    check('empty relation', solve([[], {}, 0, 2]), [[[], []], []])
elif N == 4:
    check('independent receivers', solve([[[10, 1, 4], [11, 2, 5]], {'1': 0, '2': 1}, 1, 3]), [[[[10, 4]], [[11, 5]], []], []])
    check('null receiver', solve([[[10, None, 4]], {}, 1, 3]), [[[], [[10, 4]], []], []])
    check('unmapped', solve([[[10, 7, 4]], {'1': 0}, 1, 2]), [[[], []], [[10, 'UNMAPPED']]])
    check('same receiver order', solve([[[11, 1, 4], [10, 1, 5]], {'1': 0}, 1, 2]), [[[[11, 4], [10, 5]], []], []])
    check('duplicate rows', solve([[[10, 1, 4], [10, 1, 4]], {'1': 0}, 1, 2]), [[[[10, 4], [10, 4]], []], []])
    check('mapped zero', solve([[[10, 0, 4]], {'0': 1}, 0, 2]), [[[], [[10, 4]]], []])
    check('empty relation', solve([[], {}, 0, 2]), [[[], []], []])
elif N == 5:
    check('independent receivers', solve([[[10, 1, 5], [11, 2, 6]], {'1': 0, '2': 1}, 1, 3]), [[[[10, 5]], [[11, 6]], []], []])
    check('null receiver', solve([[[10, None, 5]], {}, 1, 3]), [[[], [[10, 5]], []], []])
    check('unmapped', solve([[[10, 7, 5]], {'1': 0}, 1, 2]), [[[], []], [[10, 'UNMAPPED']]])
    check('same receiver order', solve([[[11, 1, 5], [10, 1, 6]], {'1': 0}, 1, 2]), [[[[11, 5], [10, 6]], []], []])
    check('duplicate rows', solve([[[10, 1, 5], [10, 1, 5]], {'1': 0}, 1, 2]), [[[[10, 5], [10, 5]], []], []])
    check('mapped zero', solve([[[10, 0, 5]], {'0': 1}, 0, 2]), [[[], [[10, 5]]], []])
    check('empty relation', solve([[], {}, 0, 2]), [[[], []], []])
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
independent receivers[[[[1, 1]], [[2, 2]], []], []][[[[10, 1]], [[11, 2]], []], []]Failed
null receiver[[[], [[None, 1]], []], []][[[], [[10, 1]], []], []]Failed
unmapped[[[], []], [[10, 'UNMAPPED']]][[[], []], [[10, 'UNMAPPED']]]Passed
same receiver order[[[[1, 1], [1, 2]], []], []][[[[11, 1], [10, 2]], []], []]Failed
duplicate rows[[[[1, 1], [1, 1]], []], []][[[[10, 1], [10, 1]], []], []]Failed
mapped zero[[[], [[0, 1]]], []][[[], [[10, 1]]], []]Failed
empty relation[[[], []], []][[[], []], []]Passed

SHA-256 / 369e81fea593fa62adc3fd3b29804fd85cc8faeba75318afa5c6c6335c4b1e59

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(d):
    try:
        rows,mapping,null_partition,count=d
        receivers=[[] for _ in range(count)]; rejected=[]
        for ident,key,payload in rows:
            if key is None: target=null_partition
            elif str(key) in mapping: target=mapping[str(key)]
            else: rejected.append([ident,'UNMAPPED']); continue
            receivers[target].append([payload,ident])
        return [receivers,rejected]
    except (IndexError, KeyError, ValueError, StopIteration) as exc:
        return {"representation_error": type(exc).__name__}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
if N == 1:
    check('independent receivers', solve([[[10, 1, 1], [11, 2, 2]], {'1': 0, '2': 1}, 1, 3]), [[[[10, 1]], [[11, 2]], []], []])
    check('null receiver', solve([[[10, None, 1]], {}, 1, 3]), [[[], [[10, 1]], []], []])
    check('unmapped', solve([[[10, 7, 1]], {'1': 0}, 1, 2]), [[[], []], [[10, 'UNMAPPED']]])
    check('same receiver order', solve([[[11, 1, 1], [10, 1, 2]], {'1': 0}, 1, 2]), [[[[11, 1], [10, 2]], []], []])
    check('duplicate rows', solve([[[10, 1, 1], [10, 1, 1]], {'1': 0}, 1, 2]), [[[[10, 1], [10, 1]], []], []])
    check('mapped zero', solve([[[10, 0, 1]], {'0': 1}, 0, 2]), [[[], [[10, 1]]], []])
    check('empty relation', solve([[], {}, 0, 2]), [[[], []], []])
elif N == 2:
    check('independent receivers', solve([[[10, 1, 2], [11, 2, 3]], {'1': 0, '2': 1}, 1, 3]), [[[[10, 2]], [[11, 3]], []], []])
    check('null receiver', solve([[[10, None, 2]], {}, 1, 3]), [[[], [[10, 2]], []], []])
    check('unmapped', solve([[[10, 7, 2]], {'1': 0}, 1, 2]), [[[], []], [[10, 'UNMAPPED']]])
    check('same receiver order', solve([[[11, 1, 2], [10, 1, 3]], {'1': 0}, 1, 2]), [[[[11, 2], [10, 3]], []], []])
    check('duplicate rows', solve([[[10, 1, 2], [10, 1, 2]], {'1': 0}, 1, 2]), [[[[10, 2], [10, 2]], []], []])
    check('mapped zero', solve([[[10, 0, 2]], {'0': 1}, 0, 2]), [[[], [[10, 2]]], []])
    check('empty relation', solve([[], {}, 0, 2]), [[[], []], []])
elif N == 3:
    check('independent receivers', solve([[[10, 1, 3], [11, 2, 4]], {'1': 0, '2': 1}, 1, 3]), [[[[10, 3]], [[11, 4]], []], []])
    check('null receiver', solve([[[10, None, 3]], {}, 1, 3]), [[[], [[10, 3]], []], []])
    check('unmapped', solve([[[10, 7, 3]], {'1': 0}, 1, 2]), [[[], []], [[10, 'UNMAPPED']]])
    check('same receiver order', solve([[[11, 1, 3], [10, 1, 4]], {'1': 0}, 1, 2]), [[[[11, 3], [10, 4]], []], []])
    check('duplicate rows', solve([[[10, 1, 3], [10, 1, 3]], {'1': 0}, 1, 2]), [[[[10, 3], [10, 3]], []], []])
    check('mapped zero', solve([[[10, 0, 3]], {'0': 1}, 0, 2]), [[[], [[10, 3]]], []])
    check('empty relation', solve([[], {}, 0, 2]), [[[], []], []])
elif N == 4:
    check('independent receivers', solve([[[10, 1, 4], [11, 2, 5]], {'1': 0, '2': 1}, 1, 3]), [[[[10, 4]], [[11, 5]], []], []])
    check('null receiver', solve([[[10, None, 4]], {}, 1, 3]), [[[], [[10, 4]], []], []])
    check('unmapped', solve([[[10, 7, 4]], {'1': 0}, 1, 2]), [[[], []], [[10, 'UNMAPPED']]])
    check('same receiver order', solve([[[11, 1, 4], [10, 1, 5]], {'1': 0}, 1, 2]), [[[[11, 4], [10, 5]], []], []])
    check('duplicate rows', solve([[[10, 1, 4], [10, 1, 4]], {'1': 0}, 1, 2]), [[[[10, 4], [10, 4]], []], []])
    check('mapped zero', solve([[[10, 0, 4]], {'0': 1}, 0, 2]), [[[], [[10, 4]]], []])
    check('empty relation', solve([[], {}, 0, 2]), [[[], []], []])
elif N == 5:
    check('independent receivers', solve([[[10, 1, 5], [11, 2, 6]], {'1': 0, '2': 1}, 1, 3]), [[[[10, 5]], [[11, 6]], []], []])
    check('null receiver', solve([[[10, None, 5]], {}, 1, 3]), [[[], [[10, 5]], []], []])
    check('unmapped', solve([[[10, 7, 5]], {'1': 0}, 1, 2]), [[[], []], [[10, 'UNMAPPED']]])
    check('same receiver order', solve([[[11, 1, 5], [10, 1, 6]], {'1': 0}, 1, 2]), [[[[11, 5], [10, 6]], []], []])
    check('duplicate rows', solve([[[10, 1, 5], [10, 1, 5]], {'1': 0}, 1, 2]), [[[[10, 5], [10, 5]], []], []])
    check('mapped zero', solve([[[10, 0, 5]], {'0': 1}, 0, 2]), [[[], [[10, 5]]], []])
    check('empty relation', solve([[], {}, 0, 2]), [[[], []], []])
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
independent receivers[[[[1, 10]], [[2, 11]], []], []][[[[10, 1]], [[11, 2]], []], []]Failed
null receiver[[[], [[1, 10]], []], []][[[], [[10, 1]], []], []]Failed
unmapped[[[], []], [[10, 'UNMAPPED']]][[[], []], [[10, 'UNMAPPED']]]Passed
same receiver order[[[[1, 11], [2, 10]], []], []][[[[11, 1], [10, 2]], []], []]Failed
duplicate rows[[[[1, 10], [1, 10]], []], []][[[[10, 1], [10, 1]], []], []]Failed
mapped zero[[[], [[1, 10]]], []][[[], [[10, 1]]], []]Failed
empty relation[[[], []], []][[[], []], []]Passed

SHA-256 / 93f2cdef0e2ab3436e7a6b8ba87cd40079b2296f8a60c3997fcd38c4e217d34c

HELD IN THE MEMBER ARCHIVE

The verified repair and its recorded checks are member-only.

This mechanism has 7 recorded checks per implementation. The open-access tier publishes the failure and the unsuccessful fix; the repaired source that passes every check, and the observations that prove it, are available to members.

Every case sharing this mechanism uses the same contract and the same repair, so this one record is held back for all of them.

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Verification & scope

Offline stipulated semantics over valid small inputs; no performance, concurrency, or production-engine conformance claim. This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.

Observations recorded using Python 3.12.14 at 2026-09-29T14:44:25.688797+00:00.

Case digest / 9b401aefa2de0336d3b5712dc148146be1fad172b9cb8b6aef07f0d89f6bc2e1