{"record":{"id":"7bcfbe34467da8e1","repo":"t8y2/dbx","slug":"process-candidate-name-paged-query-returned-row-7bcfbe","errorCode":null,"errorMessage":"{process.candidate.name} paged query returned {rows} rows, expected {workload['max_rows']}","messagePattern":"(.+?) paged query returned (.+?) rows, expected (.+?)","errorType":"exception","errorClass":"RuntimeError","httpStatus":null,"severity":"error","filePath":"agents/drivers/hive-go/bench/agent_compare.py","lineNumber":527,"sourceCode":"                    \"sessionId\": session_id,\n                    \"pageSize\": workload[\"page_size\"],\n                    **({\"agentSessionId\": agent_session_id} if agent_session_id else {}),\n                },\n            )\n            rows += len(page.get(\"rows\", []))\n            session_id = page.get(\"session_id\")\n            has_more = page.get(\"has_more\", False)\n    finally:\n        if session_id:\n            process.call(\n                \"close_query_session\",\n                {\n                    \"sessionId\": session_id,\n                    **({\"agentSessionId\": agent_session_id} if agent_session_id else {}),\n                },\n            )\n    if rows != workload[\"max_rows\"]:\n        raise RuntimeError(\n            f\"{process.candidate.name} paged query returned {rows} rows, \"\n            f\"expected {workload['max_rows']}\"\n        )\n    return rows\n\n\ndef sample_result(count: int, elapsed: float, samples: list[float]) -> dict:\n    summary = summarize_latencies(samples)\n    summary.update(\n        {\n            \"count\": count,\n            \"elapsed_ms\": elapsed * 1000,\n            \"ops_per_sec\": count / elapsed,\n        }\n    )\n    return summary\n\n","sourceCodeStart":509,"sourceCodeEnd":545,"githubUrl":"https://github.com/t8y2/dbx/blob/c0390bff16418b651f4728520d99adf8ce48829a/agents/drivers/hive-go/bench/agent_compare.py#L509-L545","documentation":"After draining all pages of a 'paged' workload, execute_workload asserts the accumulated row count equals workload['max_rows'] and raises RuntimeError naming the candidate when they differ. This catches truncation or over-fetch in paging behavior so benchmark results are only trusted when the query returned exactly the expected rows.","triggerScenarios":"A paging implementation drops pages (rows < max_rows), duplicates or over-fetches rows (rows > max_rows), or the underlying data changed between setup and the run; also occurs when the agent's session/page state is inconsistent across page fetches.","commonSituations":"Candidate driver with a paging bug (off-by-one in offsets, missed last page); concurrent workload mutating the table mid-benchmark; total rows fewer than max_rows because the setup data load failed partially; session reuse across workers causing skipped pages.","solutions":["Compare the returned count against max_rows and inspect the agent's paging logic for missed or duplicated pages","Verify the table actually contains max_rows rows before the benchmark (check setup/load step)","Rerun with a single worker to rule out concurrency interference","Fix the candidate driver's pagination (e.g. last-page detection, offset math)"],"exampleFix":null,"handlingStrategy":"validation","validationCode":"def verify_row_count(conn, table: str, expected: int) -> None:\n    actual = conn.execute(f\"SELECT COUNT(*) FROM {table}\").fetchone()[0]\n    if actual != expected:\n        raise SystemExit(f\"{table} has {actual} rows, expected {expected}\")\nverify_row_count(conn, \"bench_table\", workload[\"max_rows\"])  # before benchmarking","typeGuard":null,"tryCatchPattern":"try:\n    rows = execute_workload(process, paged_workload, ...)\nexcept RuntimeError as e:\n    if \"paged query returned\" in str(e):\n        print(f\"paging mismatch, rerun single-threaded to isolate: {e}\")\n        rows = execute_workload(single_process, paged_workload, ...)\n    else:\n        raise","preventionTips":["Verify table row counts match the scenario after data setup","Test each candidate's pagination with a small known dataset first","Avoid concurrent writers mutating the table during benchmarks","Add per-page row accounting in the agent to spot lost/duplicated pages"],"tags":["pagination","data-integrity","python","benchmark"],"backgroundTag":"row-count-mismatch","analyzedSha":"c0390bff16418b651f4728520d99adf8ce48829a","analyzedAt":"2026-09-05T23:05:10.900Z","contentChangedAt":"2026-09-05T23:05:10.900Z","schemaVersion":2},"datasetVersion":"2026-09-14T05:17:10.506Z"}