DB Olympics

Queries · q220 · Chief Financial Officer · week 2, night 1

Audit Sample: End-to-End Transaction Walkthrough, 2025

“For a representative sample of 2025 transactions, does the shopper payment amount, any refund, the resulting merchant payout (gross/fee/net), and the linked ledger entries all tie out consistently?”

Manager · asked the questionTobias LindqvistChief Financial Officer. New this month, previously finance director at a retailer. Preparing the 2025 annual accounts and the 2026 budget.
Analyst · planned the reportKofi MensahHypothesis-driven: states what he expects and designs reports that would prove him wrong.
Engineer · wrote the SQLGraceWrites tidy, layered CTEs with descriptive names, one step per CTE, then a final select.

Fictional people at a fictional company, each played by a language-model agent. Who they are and what they are told

  1. A business event lands on the Chief Financial Officer's desk

    Week 2

    The external auditors start the 2025 year-end audit in two weeks. They will want to see that the money adds up across the whole chain: what shoppers paid, what was refunded or credited, what merchants received in payouts, what Tidewick kept, and that invoices agree with all of it. They will also trace sample transactions end to end.

    One of the 35 events we wrote for the role play; the manager heard of it at the start of week 2 and had to cover it in that week's note. How events arise · All the events

  2. Tobias Lindqvist writes to Kofi Mensah

    The manager, at the start of week 2

    Subject: Good progress — but the audit clock is now the priority

    Kofi,

    Thanks — this is useful, and I appreciate you flagging the caveats rather than smoothing them over. A few reactions and then where I want to focus next week.

    What stood out:

    • The correction on the revenue report (off by roughly half, now fixed and cross-checked) is reassuring that you caught it, but it also makes me want a second pair of eyes before anything like this goes near the auditors.
    • The refund numbers disagreeing by 16–40% depending on which source we use is the kind of thing an auditor will ask about directly. I don't want to walk in with two different refund totals and no explanation.
    • Concentration easing as we add merchants is good context for the budget conversation — no urgent follow-up needed there this week.
    • I also saw the notes from pricing and risk this week — the free-delivery giveaway and the refund pattern on that welcome discount are small in isolation, but they're exactly the kind of "where did the money go" questions auditors and I will both ask, so I'd like a rough sense of scale rather than letting them sit as separate anecdotes.

    The big new driver: external audit starts in two weeks. They'll want to walk the full money trail — what a shopper paid, what was refunded or credited back, what the merchant was paid out, what we kept as our fee, and that it all agrees with the invoices and accounts — and they'll pick sample transactions and trace them start to finish. I'd rather we got ahead of that than react to it.

    Questions for this week, in priority order:

    1. Can we demonstrate, for a sample of transactions, that the money actually adds up end to end — shopper payment through refund/credit, payout to the merchant, and our retained fee — so we have something ready to hand the auditors rather than assembling it under time pressure?
    2. Which refund figure should I trust for the 2025 accounts, and why do the two methods disagree? I don't need the full reconciliation solved, but I need to understand the likely cause well enough to explain it credibly if asked.
    3. Where do things stand on getting our own plan-fee revenue into the picture, even approximately, so I'm not presenting half of 2025 revenue as the whole story?
    4. If there's room: roughly how much revenue or margin might be leaking through the control gaps your peers flagged this week (free deliveries to canceled customers, uncapped coupon reuse) — just enough for me to judge whether it's noise or something that belongs in front of the auditors too.

    Audit readiness (#1) is the one I most need — please make that the lead request even if it means FX and B2B receivables slip another week.

    Thanks, Tobias

  3. Kofi Mensah plans the night

    The analyst · week 2, night 1, request 1 of 3

    Audit readiness is explicitly the lead ask, so I'm using one dense report to walk a sample of real transactions end-to-end — payment → refund → merchant payout (gross/fee/net) → ledger balance — in one place, since that's literally what the auditors will do when they pick sample transactions. I folded the payout settlement check and the ledger tie-out into a single payment-grain report (12 columns, at the comfortable limit) rather than two separate reports, to leave room tonight for the other two priorities.

    For priority #2 (refund figure discrepancy), my working hypothesis going in is that this is a structural date-field mismatch rather than a data error: payments.amount_refunded gets bucketed by the original purchase's captured_at quarter, while order_returns.refund_total gets bucketed by refunded_at (when the refund actually happened) — and Yuki's finding that refunds typically land ~3 weeks after settlement supports refunds routinely crossing a quarter boundary. I'm testing that directly by measuring the lag between purchase quarter and refund quarter for 2025 returns, which should explain most of the 16-40% swings without needing a full reconciliation.

    For #4 (room permitting), I'm sizing the uncapped-coupon-reuse gap Oliver flagged, since "no usage/per-customer limit exists" is only a control gap in euros if people are actually exploiting it — I want €-at-risk from repeat redemptions by the same customer, comparable in kind to the €57k free-delivery number, so Tobias can judge scale before deciding if it goes to the auditors.

    #3 (plan-fee revenue) gets no slot tonight: I rechecked the schema and confirmed there is no table that could hold Tidewick's own platform-plan billing of merchants (plans/subscriptions/invoices here are each merchant's billing of their own customers) — this is a true data gap, not something a cleverer query can solve, so I'll report that status in prose and recommend sourcing it from the corporate billing/finance system instead.

    Audit Sample: End-to-End Transaction Walkthrough, 2025
    Question
    For a representative sample of 2025 transactions, does the shopper payment amount, any refund, the resulting merchant payout (gross/fee/net), and the linked ledger entries all tie out consistently?
    One row per
    one sampled payment captured in 2025
    Columns
    • order_number
    • merchant_name
    • currency_code
    • payment_amount (captured)
    • amount_refunded
    • net_amount (payment_amount - amount_refunded)
    • payout_item_amount (amount of this payment settled into a payout, from payout_items)
    • payout_item_fee_amount
    • payout_net_amount (payout_item_amount - payout_item_fee_amount)
    • ledger_debit_credit_diff (sum of ledger_entries.amount for this payment_id where direction='debit' minus direction='credit'; should be 0)
    • ledger_credit_total (sum of ledger_entries.amount for this payment_id where direction='credit', to compare against payment_amount)
    • reconciliation_flag ('OK' if net_amount equals payout_net_amount plus payout_item_fee_amount and ledger_debit_credit_diff is 0 and not yet settled payments are labeled 'PENDING PAYOUT', else 'CHECK')

  4. Grace writes the SQL

    The engineer · 1 dry run on the empty schema, then the submission

    Dry run 1 · STATUS: COMPILES (dry run on the empty schema, no data read)
    WITH base_payments AS (
  SELECT
    p.id AS payment_id,
    p.tenant_id,
    p.order_id,
    p.currency_code,
    p.amount AS payment_amount,
    p.amount_refunded,
    p.captured_at
  FROM payments p
  WHERE p.status IN ('captured','refunded','partially_refunded')
    AND p.captured_at >= DATE '2025-01-01'
    AND p.captured_at < DATE '2026-01-01'
    AND p.order_id IS NOT NULL
),
fx_rates AS (
  SELECT quote_code, as_of, rate
  FROM exchange_rates
  WHERE base_code = 'EUR'
),
payments_with_eur AS (
  SELECT
    bp.*,
    CASE WHEN bp.currency_code = 'EUR' THEN bp.payment_amount
         ELSE bp.payment_amount / fx.rate END AS payment_amount_eur
  FROM base_payments bp
  LEFT JOIN fx_rates fx
    ON fx.quote_code = bp.currency_code
   AND fx.as_of = CAST(bp.captured_at AS date)
),
payout_agg AS (
  SELECT payment_id, amount AS payout_item_amount, fee_amount AS payout_item_fee_amount
  FROM payout_items
),
ledger_agg AS (
  SELECT
    payment_id,
    SUM(CASE WHEN direction = 'debit' THEN amount ELSE 0 END) AS ledger_debit_total,
    SUM(CASE WHEN direction = 'credit' THEN amount ELSE 0 END) AS ledger_credit_total
  FROM ledger_entries
  WHERE payment_id IS NOT NULL
  GROUP BY payment_id
),
enriched AS (
  SELECT
    pwe.payment_id,
    pwe.tenant_id,
    pwe.order_id,
    pwe.currency_code,
    pwe.payment_amount,
    pwe.amount_refunded,
    pwe.payment_amount_eur,
    pa.payout_item_amount,
    pa.payout_item_fee_amount,
    la.ledger_debit_total,
    la.ledger_credit_total
  FROM payments_with_eur pwe
  LEFT JOIN payout_agg pa ON pa.payment_id = pwe.payment_id
  LEFT JOIN ledger_agg la ON la.payment_id = pwe.payment_id
),
tenant_top_payment AS (
  SELECT e.*, ROW_NUMBER() OVER (PARTITION BY e.tenant_id ORDER BY e.payment_amount_eur DESC) AS tenant_rn
  FROM enriched e
),
largest_sample AS (
  SELECT
    payment_id, tenant_id, order_id, currency_code, payment_amount, amount_refunded,
    payment_amount_eur, payout_item_amount, payout_item_fee_amount,
    ledger_debit_total, ledger_credit_total, 'A_LARGEST' AS sample_category
  FROM tenant_top_payment
  WHERE tenant_rn = 1
  ORDER BY payment_amount_eur DESC
  LIMIT 8
),
refund_candidates AS (
  SELECT
    e.*,
    CASE WHEN e.amount_refunded = e.payment_amount THEN 'FULL' ELSE 'PARTIAL' END AS refund_kind
  FROM enriched e
  WHERE e.amount_refunded > 0
),
refund_ranked AS (
  SELECT
    rc.*,
    ROW_NUMBER() OVER (PARTITION BY rc.tenant_id, rc.refund_kind ORDER BY rc.amount_refunded DESC) AS tenant_refund_rn
  FROM refund_candidates rc
),
refund_sample AS (
  (SELECT payment_id, tenant_id, order_id, currency_code, payment_amount, amount_refunded,
          payment_amount_eur, payout_item_amount, payout_item_fee_amount,
          ledger_debit_total, ledger_credit_total, 'B_REFUND' AS sample_category
   FROM refund_ranked WHERE refund_kind = 'FULL' AND tenant_refund_rn = 1
   ORDER BY amount_refunded DESC LIMIT 4)
  UNION ALL
  (SELECT payment_id, tenant_id, order_id, currency_code, payment_amount, amount_refunded,
          payment_amount_eur, payout_item_amount, payout_item_fee_amount,
          ledger_debit_total, ledger_credit_total, 'B_REFUND' AS sample_category
   FROM refund_ranked WHERE refund_kind = 'PARTIAL' AND tenant_refund_rn = 1
   ORDER BY amount_refunded DESC LIMIT 4)
),
tiled AS (
  SELECT e.*, NTILE(9) OVER (ORDER BY e.payment_id) AS tile
  FROM enriched e
),
tiled_ranked AS (
  SELECT
    t.*,
    ROW_NUMBER() OVER (PARTITION BY t.tile ORDER BY (t.payout_item_amount IS NULL) DESC, t.payment_id) AS tile_rn
  FROM tiled t
),
typical_sample AS (
  SELECT
    payment_id, tenant_id, order_id, currency_code, payment_amount, amount_refunded,
    payment_amount_eur, payout_item_amount, payout_item_fee_amount,
    ledger_debit_total, ledger_credit_total, 'C_TYPICAL' AS sample_category
  FROM tiled_ranked
  WHERE tile_rn = 1
),
all_samples AS (
  SELECT * FROM largest_sample
  UNION ALL
  SELECT * FROM refund_sample
  UNION ALL
  SELECT * FROM typical_sample
),
final AS (
  SELECT
    s.payment_id,
    o.order_number,
    t.name AS merchant_name,
    s.currency_code,
    s.payment_amount,
    s.amount_refunded,
    (s.payment_amount - s.amount_refunded) AS net_amount,
    s.payout_item_amount,
    s.payout_item_fee_amount,
    (s.payout_item_amount - s.payout_item_fee_amount) AS payout_net_amount,
    (COALESCE(s.ledger_debit_total,0) - COALESCE(s.ledger_credit_total,0)) AS ledger_debit_credit_diff,
    s.ledger_credit_total,
    CASE
      WHEN s.payout_item_amount IS NULL THEN 'PENDING PAYOUT'
      WHEN (s.payment_amount - s.amount_refunded) = s.payout_item_amount
           AND (COALESCE(s.ledger_debit_total,0) - COALESCE(s.ledger_credit_total,0)) = 0
        THEN 'OK'
      ELSE 'CHECK'
    END AS reconciliation_flag,
    s.sample_category
  FROM all_samples s
  JOIN orders o ON o.id = s.order_id
  JOIN tenants t ON t.id = s.tenant_id
)
SELECT
  order_number,
  merchant_name,
  currency_code,
  payment_amount,
  amount_refunded,
  net_amount,
  payout_item_amount,
  payout_item_fee_amount,
  payout_net_amount,
  ledger_debit_credit_diff,
  ledger_credit_total,
  reconciliation_flag
FROM final
ORDER BY
  CASE sample_category WHEN 'A_LARGEST' THEN 1 WHEN 'B_REFUND' THEN 2 ELSE 3 END,
  payment_amount DESC,
  payment_id

    “Query compiles and returns exactly the 12 requested columns. Submitting.”

    Submitted · the SQL of the last dry run, unchanged · Submitted to tonight's batch. Your work on this request is done.

    “Submitted. Summary of the approach: - Base set: payments with status in (captured/refunded/partially_refunded), captured_at in 2025, and a linked order (needed for order_number). - Enrichment: left-joined payout_items (1:1 by payment) and ledger_entries (aggregated debit/credit totals per payment), plus an EUR-converted amount via exchange_rates used only for ranking. - Sampling: - A — Largest (8 rows): each tenant's single biggest 2025 payment (EUR-ranked), then the top 8 tenants — guarantees tenant spread. - B — Refunds (8 rows): top 4 tenants by largest fully-refunded payment + top 4 by largest partially-refunded payment. - C — Typical (9 rows): NTILE(9) over payments.id as the deterministic pseudo-random split, preferring unmatched-payout rows within each tile when present. - Reconciliation: PENDING PAYOUT when no payout_items row exists yet; OK when net amount matches the settled payout amount and ledger debits/credits balance to zero; CHECK otherwise. - All monetary columns stay in each payment's native currency_code as requested, so the diff/flag checks are exact rather than FX-rounded. One caveat noted to the analyst: the "at least 2 unmatched-payout" condition in category C is favored by the tiling logic but isn't a hard guarantee if payouts happen to cover every tile.”

  5. The report comes back overnight

    As Kofi Mensah saw it, from the small dataset the agents worked on

    order_number | merchant_name                 | currency_code | payment_amount | amount_refunded |  net_amount | payout_item_amount | payout_item_fee_amount | payout_net_amount | ledger_debit_credit_diff | ledger_credit_total | reconciliation_flag
-------------+-------------------------------+---------------+----------------+-----------------+-------------+--------------------+------------------------+-------------------+--------------------------+---------------------+--------------------
SO-100280    | OfficeHub Nordic              | NOK           |    340796.0000 |          0.0000 | 340796.0000 |        340796.0000 |              5112.1900 |       335683.8100 |                   0.0000 |         340796.0000 | OK                 
SO-100285    | Castell Fasteners             | USD           |     51558.1600 |          0.0000 |  51558.1600 |         51558.1600 |              1753.3300 |        49804.8300 |                   0.0000 |          51558.1600 | OK                 
SO-100090    | Deskline Supplies             | GBP           |     34463.1600 |          0.0000 |  34463.1600 |               NULL |                   NULL |              NULL |                   0.0000 |          34463.1600 | PENDING PAYOUT     
SO-100380    | Kontor24 Bürobedarf           | EUR           |     31036.7400 |          0.0000 |  31036.7400 |               NULL |                   NULL |              NULL |                   0.0000 |          31036.7400 | PENDING PAYOUT     
SO-100573    | Ballycorran Industrial Supply | EUR           |     29905.1900 |          0.0000 |  29905.1900 |               NULL |                   NULL |              NULL |                   0.0000 |          29905.1900 | PENDING PAYOUT     
SO-100355    | Midland Safety Wear           | EUR           |     24012.1900 |          0.0000 |  24012.1900 |         24012.1900 |               360.4300 |        23651.7600 |                   0.0000 |          24012.1900 | OK                 
#1664        | Ampfeld Elektronik            | EUR           |     22391.5900 |          0.0000 |  22391.5900 |         22391.5900 |               336.1200 |        22055.4700 |                   0.0000 |          22391.5900 | OK                 
SO-100118    | Hanse Industriebedarf         | EUR           |     14834.4900 |          0.0000 |  14834.4900 |               NULL |                   NULL |              NULL |                   0.0000 |          14834.4900 | PENDING PAYOUT     
SO-100363    | OfficeHub Nordic              | NOK           |    265275.1500 |     265275.1500 |      0.0000 |        265275.1500 |             12998.4800 |       252276.6700 |                   0.0000 |         530550.3000 | CHECK              
#1179        | Fell & Fjell                  | DKK           |     34885.8500 |      34522.9000 |    362.9500 |         34885.8500 |               488.6500 |        34397.2000 |                   0.0000 |          69408.7500 | CHECK              
CC-100015    | Courtside Collective          | NOK           |     17158.5000 |      17158.5000 |      0.0000 |         17158.5000 |               257.6300 |        16900.8700 |                   0.0000 |          34317.0000 | CHECK              
#1727        | Ampfeld Elektronik            | EUR           |     16619.9900 |      16619.9900 |      0.0000 |         16619.9900 |               232.9300 |        16387.0600 |                   0.0000 |          33239.9800 | CHECK              
SO-100835    | Ballycorran Industrial Supply | EUR           |     15174.5200 |      15174.5200 |      0.0000 |         15174.5200 |               227.8700 |        14946.6500 |                   0.0000 |          30349.0400 | CHECK              
SO-100608    | Ballycorran Industrial Supply | EUR           |      9150.4400 |       8402.4600 |    747.9800 |          9150.4400 |               137.5100 |         9012.9300 |                   0.0000 |          17552.9000 | CHECK              
SO-100307    | Midland Safety Wear           | EUR           |      7702.3700 |       4122.4400 |   3579.9300 |          7702.3700 |               115.7900 |         7586.5800 |                   0.0000 |          11824.8100 | CHECK              
#1004        | Halden Boots                  | SEK           |      6560.0000 |       4102.0000 |   2458.0000 |          6560.0000 |                98.6500 |         6461.3500 |                   0.0000 |          10662.0000 | CHECK              
SO-100400    | OfficeHub Nordic              | NOK           |     17941.0500 |          0.0000 |  17941.0500 |               NULL |                   NULL |              NULL |                   0.0000 |          17941.0500 | PENDING PAYOUT     
SO-100740    | Ballycorran Industrial Supply | EUR           |      4957.5800 |          0.0000 |   4957.5800 |               NULL |                   NULL |              NULL |                   0.0000 |           4957.5800 | PENDING PAYOUT     
SO-100233    | Castell Fasteners             | USD           |       752.9100 |          0.0000 |    752.9100 |               NULL |                   NULL |              NULL |                   0.0000 |            805.5600 | PENDING PAYOUT     
SO-100519    | Ballycorran Industrial Supply | EUR           |       704.9700 |          0.0000 |    704.9700 |               NULL |                   NULL |              NULL |                   0.0000 |            704.9700 | PENDING PAYOUT     
SO-100273    | Midland Safety Wear           | EUR           |       240.4000 |          0.0000 |    240.4000 |               NULL |                   NULL |              NULL |                   0.0000 |            240.4000 | PENDING PAYOUT     
SO-100357    | Castell Fasteners             | USD           |        92.4400 |          0.0000 |     92.4400 |               NULL |                   NULL |              NULL |                   0.0000 |             92.4400 | PENDING PAYOUT     
SO-100084    | Polder Packaging              | EUR           |        88.8900 |          0.0000 |     88.8900 |               NULL |                   NULL |              NULL |                   0.0000 |             88.8900 | PENDING PAYOUT     
SO-100266    | Castell Fasteners             | USD           |        57.3100 |          0.0000 |     57.3100 |               NULL |                   NULL |              NULL |                   0.0000 |             57.3100 | PENDING PAYOUT     
#3307        | Marrowby & Vane               | GBP           |        20.0000 |          0.0000 |     20.0000 |               NULL |                   NULL |              NULL |                   0.0000 |                NULL | PENDING PAYOUT     
(25 rows)

  6. What came of it

    The memo and the queries that followed; links found by title, so inferred

    Later queries that build on this report:

  7. It becomes benchmark query q220

    Changed only where the benchmark needs the same result on every system

    • spellingfetch first (3×)
    • determinismtie-breaker: payment_id is unique in enriched (payout_items.payment_id is unique, ledger_agg is grouped by payment_id)
    • determinismtie-breaker: payment_id is unique
    • determinismtie-breaker: payment_id is unique
    • determinismtie-breaker: payment_id is unique
    • determinismtie-breaker: payment_id is unique
    • numericsdocs/NUMERICS.md: x / exchange rate cast to NUMERIC(18,6)
    • made explicita selected t.col gets AS col, its standard name made explicit (25×)
    • determinismthe standard leaves the place of NULLs in a sort to the implementation: NULLS LAST ascending, NULLS FIRST descending, as in the reference results (16×)
    • placeholderfetch first (3×)
    The benchmark text, against the submitted SQL
    WITH base_payments AS (  SELECT    p.id AS payment_id,    p.tenant_id,    p.order_id,    p.currency_code,    p.tenant_id AS tenant_id,    p.order_id AS order_id,    p.currency_code AS currency_code,    p.amount AS payment_amount,    p.amount_refunded,    p.captured_at    p.amount_refunded AS amount_refunded,    p.captured_at AS captured_at  FROM payments p  WHERE p.status IN ('captured','refunded','partially_refunded')    AND p.captured_at >= DATE '2025-01-01'    AND p.captured_at < DATE '2026-01-01'    AND p.order_id IS NOT NULL),fx_rates AS (  SELECT quote_code, as_of, rate  FROM exchange_rates  WHERE base_code = 'EUR'),payments_with_eur AS (  SELECT    bp.*,    CASE WHEN bp.currency_code = 'EUR' THEN bp.payment_amount         ELSE bp.payment_amount / fx.rate END AS payment_amount_eur         ELSE CAST(bp.payment_amount / fx.rate AS NUMERIC(18,6)) END AS payment_amount_eur  FROM base_payments bp  LEFT JOIN fx_rates fx    ON fx.quote_code = bp.currency_code   AND fx.as_of = CAST(bp.captured_at AS date)),payout_agg AS (  SELECT payment_id, amount AS payout_item_amount, fee_amount AS payout_item_fee_amount  FROM payout_items),ledger_agg AS (  SELECT    payment_id,    SUM(CASE WHEN direction = 'debit' THEN amount ELSE 0 END) AS ledger_debit_total,    SUM(CASE WHEN direction = 'credit' THEN amount ELSE 0 END) AS ledger_credit_total  FROM ledger_entries  WHERE payment_id IS NOT NULL  GROUP BY payment_id),enriched AS (  SELECT    pwe.payment_id,    pwe.tenant_id,    pwe.order_id,    pwe.currency_code,    pwe.payment_amount,    pwe.amount_refunded,    pwe.payment_amount_eur,    pa.payout_item_amount,    pa.payout_item_fee_amount,    la.ledger_debit_total,    la.ledger_credit_total    pwe.payment_id AS payment_id,    pwe.tenant_id AS tenant_id,    pwe.order_id AS order_id,    pwe.currency_code AS currency_code,    pwe.payment_amount AS payment_amount,    pwe.amount_refunded AS amount_refunded,    pwe.payment_amount_eur AS payment_amount_eur,    pa.payout_item_amount AS payout_item_amount,    pa.payout_item_fee_amount AS payout_item_fee_amount,    la.ledger_debit_total AS ledger_debit_total,    la.ledger_credit_total AS ledger_credit_total  FROM payments_with_eur pwe  LEFT JOIN payout_agg pa ON pa.payment_id = pwe.payment_id  LEFT JOIN ledger_agg la ON la.payment_id = pwe.payment_id),tenant_top_payment AS (  SELECT e.*, ROW_NUMBER() OVER (PARTITION BY e.tenant_id ORDER BY e.payment_amount_eur DESC) AS tenant_rn  SELECT e.*, ROW_NUMBER() OVER (PARTITION BY e.tenant_id ORDER BY e.payment_amount_eur DESC NULLS FIRST, e.payment_id NULLS LAST) AS tenant_rn  FROM enriched e),largest_sample AS (  SELECT    payment_id, tenant_id, order_id, currency_code, payment_amount, amount_refunded,    payment_amount_eur, payout_item_amount, payout_item_fee_amount,    ledger_debit_total, ledger_credit_total, 'A_LARGEST' AS sample_category  FROM tenant_top_payment  WHERE tenant_rn = 1  ORDER BY payment_amount_eur DESC  LIMIT 8  ORDER BY payment_amount_eur DESC NULLS FIRST, payment_id NULLS LAST  {{fetch_first(8)}}),refund_candidates AS (  SELECT    e.*,    CASE WHEN e.amount_refunded = e.payment_amount THEN 'FULL' ELSE 'PARTIAL' END AS refund_kind  FROM enriched e  WHERE e.amount_refunded > 0),refund_ranked AS (  SELECT    rc.*,    ROW_NUMBER() OVER (PARTITION BY rc.tenant_id, rc.refund_kind ORDER BY rc.amount_refunded DESC) AS tenant_refund_rn    ROW_NUMBER() OVER (PARTITION BY rc.tenant_id, rc.refund_kind ORDER BY rc.amount_refunded DESC NULLS FIRST, rc.payment_id NULLS LAST) AS tenant_refund_rn  FROM refund_candidates rc),refund_sample AS (  (SELECT payment_id, tenant_id, order_id, currency_code, payment_amount, amount_refunded,          payment_amount_eur, payout_item_amount, payout_item_fee_amount,          ledger_debit_total, ledger_credit_total, 'B_REFUND' AS sample_category   FROM refund_ranked WHERE refund_kind = 'FULL' AND tenant_refund_rn = 1   ORDER BY amount_refunded DESC LIMIT 4)   ORDER BY amount_refunded DESC NULLS FIRST, payment_id NULLS LAST {{fetch_first(4)}})  UNION ALL  (SELECT payment_id, tenant_id, order_id, currency_code, payment_amount, amount_refunded,          payment_amount_eur, payout_item_amount, payout_item_fee_amount,          ledger_debit_total, ledger_credit_total, 'B_REFUND' AS sample_category   FROM refund_ranked WHERE refund_kind = 'PARTIAL' AND tenant_refund_rn = 1   ORDER BY amount_refunded DESC LIMIT 4)   ORDER BY amount_refunded DESC NULLS FIRST, payment_id NULLS LAST {{fetch_first(4)}})),tiled AS (  SELECT e.*, NTILE(9) OVER (ORDER BY e.payment_id) AS tile  SELECT e.*, NTILE(9) OVER (ORDER BY e.payment_id NULLS LAST) AS tile  FROM enriched e),tiled_ranked AS (  SELECT    t.*,    ROW_NUMBER() OVER (PARTITION BY t.tile ORDER BY (t.payout_item_amount IS NULL) DESC, t.payment_id) AS tile_rn    ROW_NUMBER() OVER (PARTITION BY t.tile ORDER BY (t.payout_item_amount IS NULL) DESC NULLS FIRST, t.payment_id NULLS LAST) AS tile_rn  FROM tiled t),typical_sample AS (  SELECT    payment_id, tenant_id, order_id, currency_code, payment_amount, amount_refunded,    payment_amount_eur, payout_item_amount, payout_item_fee_amount,    ledger_debit_total, ledger_credit_total, 'C_TYPICAL' AS sample_category  FROM tiled_ranked  WHERE tile_rn = 1),all_samples AS (  SELECT * FROM largest_sample  UNION ALL  SELECT * FROM refund_sample  UNION ALL  SELECT * FROM typical_sample),final AS (  SELECT    s.payment_id,    o.order_number,    s.payment_id AS payment_id,    o.order_number AS order_number,    t.name AS merchant_name,    s.currency_code,    s.payment_amount,    s.amount_refunded,    s.currency_code AS currency_code,    s.payment_amount AS payment_amount,    s.amount_refunded AS amount_refunded,    (s.payment_amount - s.amount_refunded) AS net_amount,    s.payout_item_amount,    s.payout_item_fee_amount,    s.payout_item_amount AS payout_item_amount,    s.payout_item_fee_amount AS payout_item_fee_amount,    (s.payout_item_amount - s.payout_item_fee_amount) AS payout_net_amount,    (COALESCE(s.ledger_debit_total,0) - COALESCE(s.ledger_credit_total,0)) AS ledger_debit_credit_diff,    s.ledger_credit_total,    s.ledger_credit_total AS ledger_credit_total,    CASE      WHEN s.payout_item_amount IS NULL THEN 'PENDING PAYOUT'      WHEN (s.payment_amount - s.amount_refunded) = s.payout_item_amount           AND (COALESCE(s.ledger_debit_total,0) - COALESCE(s.ledger_credit_total,0)) = 0        THEN 'OK'      ELSE 'CHECK'    END AS reconciliation_flag,    s.sample_category    s.sample_category AS sample_category  FROM all_samples s  JOIN orders o ON o.id = s.order_id  JOIN tenants t ON t.id = s.tenant_id)SELECT  order_number,  merchant_name,  currency_code,  payment_amount,  amount_refunded,  net_amount,  payout_item_amount,  payout_item_fee_amount,  payout_net_amount,  ledger_debit_credit_diff,  ledger_credit_total,  reconciliation_flagFROM finalORDER BY  CASE sample_category WHEN 'A_LARGEST' THEN 1 WHEN 'B_REFUND' THEN 2 ELSE 3 END,  payment_amount DESC,  payment_id  CASE sample_category WHEN 'A_LARGEST' THEN 1 WHEN 'B_REFUND' THEN 2 ELSE 3 END NULLS LAST,  payment_amount DESC NULLS FIRST,  payment_id NULLS LAST

    As each system received it; highlighted, the parts spelled for that system

    WITH base_payments AS (
  SELECT
    p.id AS payment_id,
    p.tenant_id AS tenant_id,
    p.order_id AS order_id,
    p.currency_code AS currency_code,
    p.amount AS payment_amount,
    p.amount_refunded AS amount_refunded,
    p.captured_at AS captured_at
  FROM payments p
  WHERE p.status IN ('captured','refunded','partially_refunded')
    AND p.captured_at >= DATE '2025-01-01'
    AND p.captured_at < DATE '2026-01-01'
    AND p.order_id IS NOT NULL
),
fx_rates AS (
  SELECT quote_code, as_of, rate
  FROM exchange_rates
  WHERE base_code = 'EUR'
),
payments_with_eur AS (
  SELECT
    bp.*,
    CASE WHEN bp.currency_code = 'EUR' THEN bp.payment_amount
         ELSE CAST(bp.payment_amount / fx.rate AS NUMERIC(18,6)) END AS payment_amount_eur
  FROM base_payments bp
  LEFT JOIN fx_rates fx
    ON fx.quote_code = bp.currency_code
   AND fx.as_of = CAST(bp.captured_at AS date)
),
payout_agg AS (
  SELECT payment_id, amount AS payout_item_amount, fee_amount AS payout_item_fee_amount
  FROM payout_items
),
ledger_agg AS (
  SELECT
    payment_id,
    SUM(CASE WHEN direction = 'debit' THEN amount ELSE 0 END) AS ledger_debit_total,
    SUM(CASE WHEN direction = 'credit' THEN amount ELSE 0 END) AS ledger_credit_total
  FROM ledger_entries
  WHERE payment_id IS NOT NULL
  GROUP BY payment_id
),
enriched AS (
  SELECT
    pwe.payment_id AS payment_id,
    pwe.tenant_id AS tenant_id,
    pwe.order_id AS order_id,
    pwe.currency_code AS currency_code,
    pwe.payment_amount AS payment_amount,
    pwe.amount_refunded AS amount_refunded,
    pwe.payment_amount_eur AS payment_amount_eur,
    pa.payout_item_amount AS payout_item_amount,
    pa.payout_item_fee_amount AS payout_item_fee_amount,
    la.ledger_debit_total AS ledger_debit_total,
    la.ledger_credit_total AS ledger_credit_total
  FROM payments_with_eur pwe
  LEFT JOIN payout_agg pa ON pa.payment_id = pwe.payment_id
  LEFT JOIN ledger_agg la ON la.payment_id = pwe.payment_id
),
tenant_top_payment AS (
  SELECT e.*, ROW_NUMBER() OVER (PARTITION BY e.tenant_id ORDER BY e.payment_amount_eur DESC NULLS FIRST, e.payment_id NULLS LAST) AS tenant_rn
  FROM enriched e
),
largest_sample AS (
  SELECT
    payment_id, tenant_id, order_id, currency_code, payment_amount, amount_refunded,
    payment_amount_eur, payout_item_amount, payout_item_fee_amount,
    ledger_debit_total, ledger_credit_total, 'A_LARGEST' AS sample_category
  FROM tenant_top_payment
  WHERE tenant_rn = 1
  ORDER BY payment_amount_eur DESC NULLS FIRST, payment_id NULLS LAST
  FETCH FIRST 8 ROWS ONLY
),
refund_candidates AS (
  SELECT
    e.*,
    CASE WHEN e.amount_refunded = e.payment_amount THEN 'FULL' ELSE 'PARTIAL' END AS refund_kind
  FROM enriched e
  WHERE e.amount_refunded > 0
),
refund_ranked AS (
  SELECT
    rc.*,
    ROW_NUMBER() OVER (PARTITION BY rc.tenant_id, rc.refund_kind ORDER BY rc.amount_refunded DESC NULLS FIRST, rc.payment_id NULLS LAST) AS tenant_refund_rn
  FROM refund_candidates rc
),
refund_sample AS (
  (SELECT payment_id, tenant_id, order_id, currency_code, payment_amount, amount_refunded,
          payment_amount_eur, payout_item_amount, payout_item_fee_amount,
          ledger_debit_total, ledger_credit_total, 'B_REFUND' AS sample_category
   FROM refund_ranked WHERE refund_kind = 'FULL' AND tenant_refund_rn = 1
   ORDER BY amount_refunded DESC NULLS FIRST, payment_id NULLS LAST FETCH FIRST 4 ROWS ONLY)
  UNION ALL
  (SELECT payment_id, tenant_id, order_id, currency_code, payment_amount, amount_refunded,
          payment_amount_eur, payout_item_amount, payout_item_fee_amount,
          ledger_debit_total, ledger_credit_total, 'B_REFUND' AS sample_category
   FROM refund_ranked WHERE refund_kind = 'PARTIAL' AND tenant_refund_rn = 1
   ORDER BY amount_refunded DESC NULLS FIRST, payment_id NULLS LAST FETCH FIRST 4 ROWS ONLY)
),
tiled AS (
  SELECT e.*, NTILE(9) OVER (ORDER BY e.payment_id NULLS LAST) AS tile
  FROM enriched e
),
tiled_ranked AS (
  SELECT
    t.*,
    ROW_NUMBER() OVER (PARTITION BY t.tile ORDER BY (t.payout_item_amount IS NULL) DESC NULLS FIRST, t.payment_id NULLS LAST) AS tile_rn
  FROM tiled t
),
typical_sample AS (
  SELECT
    payment_id, tenant_id, order_id, currency_code, payment_amount, amount_refunded,
    payment_amount_eur, payout_item_amount, payout_item_fee_amount,
    ledger_debit_total, ledger_credit_total, 'C_TYPICAL' AS sample_category
  FROM tiled_ranked
  WHERE tile_rn = 1
),
all_samples AS (
  SELECT * FROM largest_sample
  UNION ALL
  SELECT * FROM refund_sample
  UNION ALL
  SELECT * FROM typical_sample
),
final AS (
  SELECT
    s.payment_id AS payment_id,
    o.order_number AS order_number,
    t.name AS merchant_name,
    s.currency_code AS currency_code,
    s.payment_amount AS payment_amount,
    s.amount_refunded AS amount_refunded,
    (s.payment_amount - s.amount_refunded) AS net_amount,
    s.payout_item_amount AS payout_item_amount,
    s.payout_item_fee_amount AS payout_item_fee_amount,
    (s.payout_item_amount - s.payout_item_fee_amount) AS payout_net_amount,
    (COALESCE(s.ledger_debit_total,0) - COALESCE(s.ledger_credit_total,0)) AS ledger_debit_credit_diff,
    s.ledger_credit_total AS ledger_credit_total,
    CASE
      WHEN s.payout_item_amount IS NULL THEN 'PENDING PAYOUT'
      WHEN (s.payment_amount - s.amount_refunded) = s.payout_item_amount
           AND (COALESCE(s.ledger_debit_total,0) - COALESCE(s.ledger_credit_total,0)) = 0
        THEN 'OK'
      ELSE 'CHECK'
    END AS reconciliation_flag,
    s.sample_category AS sample_category
  FROM all_samples s
  JOIN orders o ON o.id = s.order_id
  JOIN tenants t ON t.id = s.tenant_id
)
SELECT
  order_number,
  merchant_name,
  currency_code,
  payment_amount,
  amount_refunded,
  net_amount,
  payout_item_amount,
  payout_item_fee_amount,
  payout_net_amount,
  ledger_debit_credit_diff,
  ledger_credit_total,
  reconciliation_flag
FROM final
ORDER BY
  CASE sample_category WHEN 'A_LARGEST' THEN 1 WHEN 'B_REFUND' THEN 2 ELSE 3 END NULLS LAST,
  payment_amount DESC NULLS FIRST,
  payment_id NULLS LAST
    1 s10 s100 sHyper1.73 sDuckDB1.80 sGizmoSQL1.59 sclickhouse_brew12.5 sFirebolterrorDataFusionerrorClickHouseerror
    • Firebolt{ "errors": [ { "description": "Line 25, Column 38: Operations between decimals with different precision and scale is not supported at the moment. Explicitly cast one of the decimals to other decimal precision and scale." } ], "query": { "query_id": "8c3b00c6-606e-41c7-b096-a7a38bfa8f9d", "query_lab
    • DataFusionResources exhausted: Failed to allocate additional 805.9 MB for ExternalSorter[4] with 0.0 B already allocated for this reservation - 409.6 MB remain available for the total memory pool: fair(pool_size: 153.6 GB)
    • ClickHouseCode: 69. DB::Exception: Decimal result's scale is less than argument's one: while executing function divide on arguments __table8.payment_amount Decimal(14, 4) Decimal64(size = 0), __table10.rate Nullable(Decimal(12, 6)) Nullable(size = 0, Decimal64(size = 0), UInt8(size = 0)). (ARGUMENT_OUT_OF_BOU

    Scale factor 1000, c8a.24xlarge, after the last load. q220 on the start page, with every configuration.

  8. Everything, as recorded

    The agents' own records, as the role play wrote them; only the personal data of the person who ran it is redacted

    Grace's whole session, 7 turns
    • The request, as Grace received it
      Report request from Kofi Mensah (analyst for the Chief Financial Officer):

Title: Audit Sample: End-to-End Transaction Walkthrough, 2025
Question: For a representative sample of 2025 transactions, does the shopper payment amount, any refund, the resulting merchant payout (gross/fee/net), and the linked ledger entries all tie out consistently?
Grain: one sampled payment captured in 2025
Columns:
- order_number
- merchant_name
- currency_code
- payment_amount (captured)
- amount_refunded
- net_amount (payment_amount - amount_refunded)
- payout_item_amount (amount of this payment settled into a payout, from payout_items)
- payout_item_fee_amount
- payout_net_amount (payout_item_amount - payout_item_fee_amount)
- ledger_debit_credit_diff (sum of ledger_entries.amount for this payment_id where direction='debit' minus direction='credit'; should be 0)
- ledger_credit_total (sum of ledger_entries.amount for this payment_id where direction='credit', to compare against payment_amount)
- reconciliation_flag ('OK' if net_amount equals payout_net_amount plus payout_item_fee_amount and ledger_debit_credit_diff is 0 and not yet settled payments are labeled 'PENDING PAYOUT', else 'CHECK')
Details: Source: payments (status captured/refunded/partially_refunded, captured_at in 2025) as the base. LEFT JOIN payout_items on payment_id (some payments may not be in a payout yet — show as NULL, not excluded). LEFT JOIN ledger_entries on payment_id, aggregated by direction. Join orders on payments.order_id for order_number, and tenants for merchant_name. Build the sample as: (a) the 8 largest payments by payment_amount (converted to EUR for ranking only, print native currency), spread across different tenants where possible; (b) 8 payments with amount_refunded > 0, choosing a mix of fully refunded (amount_refunded = amount) and partially refunded, across different tenants; (c) 9 additional payments chosen by taking every Nth row ordered by payments.id (deterministic pseudo-random) to represent typical/unremarkable transactions, including at least 2 that have no matching payout_items row yet if any exist. Do not convert money columns to EUR (keep each row in its own currency_code so the diff/reconciliation checks are exact, not rounded by conversion). Order by sample category then by payment_amount descending within category; 25 rows total.

Check your query with the warehouse's dry_run tool, then hand it in with submit.
    • Grace calls dry_run
      WITH base_payments AS (
  SELECT
    p.id AS payment_id,
    p.tenant_id,
    p.order_id,
    p.currency_code,
    p.amount AS payment_amount,
    p.amount_refunded,
    p.captured_at
  FROM payments p
  WHERE p.status IN ('captured','refunded','partially_refunded')
    AND p.captured_at >= DATE '2025-01-01'
    AND p.captured_at < DATE '2026-01-01'
    AND p.order_id IS NOT NULL
),
fx_rates AS (
  SELECT quote_code, as_of, rate
  FROM exchange_rates
  WHERE base_code = 'EUR'
),
payments_with_eur AS (
  SELECT
    bp.*,
    CASE WHEN bp.currency_code = 'EUR' THEN bp.payment_amount
         ELSE bp.payment_amount / fx.rate END AS payment_amount_eur
  FROM base_payments bp
  LEFT JOIN fx_rates fx
    ON fx.quote_code = bp.currency_code
   AND fx.as_of = CAST(bp.captured_at AS date)
),
payout_agg AS (
  SELECT payment_id, amount AS payout_item_amount, fee_amount AS payout_item_fee_amount
  FROM payout_items
),
ledger_agg AS (
  SELECT
    payment_id,
    SUM(CASE WHEN direction = 'debit' THEN amount ELSE 0 END) AS ledger_debit_total,
    SUM(CASE WHEN direction = 'credit' THEN amount ELSE 0 END) AS ledger_credit_total
  FROM ledger_entries
  WHERE payment_id IS NOT NULL
  GROUP BY payment_id
),
enriched AS (
  SELECT
    pwe.payment_id,
    pwe.tenant_id,
    pwe.order_id,
    pwe.currency_code,
    pwe.payment_amount,
    pwe.amount_refunded,
    pwe.payment_amount_eur,
    pa.payout_item_amount,
    pa.payout_item_fee_amount,
    la.ledger_debit_total,
    la.ledger_credit_total
  FROM payments_with_eur pwe
  LEFT JOIN payout_agg pa ON pa.payment_id = pwe.payment_id
  LEFT JOIN ledger_agg la ON la.payment_id = pwe.payment_id
),
tenant_top_payment AS (
  SELECT e.*, ROW_NUMBER() OVER (PARTITION BY e.tenant_id ORDER BY e.payment_amount_eur DESC) AS tenant_rn
  FROM enriched e
),
largest_sample AS (
  SELECT
    payment_id, tenant_id, order_id, currency_code, payment_amount, amount_refunded,
    payment_amount_eur, payout_item_amount, payout_item_fee_amount,
    ledger_debit_total, ledger_credit_total, 'A_LARGEST' AS sample_category
  FROM tenant_top_payment
  WHERE tenant_rn = 1
  ORDER BY payment_amount_eur DESC
  LIMIT 8
),
refund_candidates AS (
  SELECT
    e.*,
    CASE WHEN e.amount_refunded = e.payment_amount THEN 'FULL' ELSE 'PARTIAL' END AS refund_kind
  FROM enriched e
  WHERE e.amount_refunded > 0
),
refund_ranked AS (
  SELECT
    rc.*,
    ROW_NUMBER() OVER (PARTITION BY rc.tenant_id, rc.refund_kind ORDER BY rc.amount_refunded DESC) AS tenant_refund_rn
  FROM refund_candidates rc
),
refund_sample AS (
  (SELECT payment_id, tenant_id, order_id, currency_code, payment_amount, amount_refunded,
          payment_amount_eur, payout_item_amount, payout_item_fee_amount,
          ledger_debit_total, ledger_credit_total, 'B_REFUND' AS sample_category
   FROM refund_ranked WHERE refund_kind = 'FULL' AND tenant_refund_rn = 1
   ORDER BY amount_refunded DESC LIMIT 4)
  UNION ALL
  (SELECT payment_id, tenant_id, order_id, currency_code, payment_amount, amount_refunded,
          payment_amount_eur, payout_item_amount, payout_item_fee_amount,
          ledger_debit_total, ledger_credit_total, 'B_REFUND' AS sample_category
   FROM refund_ranked WHERE refund_kind = 'PARTIAL' AND tenant_refund_rn = 1
   ORDER BY amount_refunded DESC LIMIT 4)
),
tiled AS (
  SELECT e.*, NTILE(9) OVER (ORDER BY e.payment_id) AS tile
  FROM enriched e
),
tiled_ranked AS (
  SELECT
    t.*,
    ROW_NUMBER() OVER (PARTITION BY t.tile ORDER BY (t.payout_item_amount IS NULL) DESC, t.payment_id) AS tile_rn
  FROM tiled t
),
typical_sample AS (
  SELECT
    payment_id, tenant_id, order_id, currency_code, payment_amount, amount_refunded,
    payment_amount_eur, payout_item_amount, payout_item_fee_amount,
    ledger_debit_total, ledger_credit_total, 'C_TYPICAL' AS sample_category
  FROM tiled_ranked
  WHERE tile_rn = 1
),
all_samples AS (
  SELECT * FROM largest_sample
  UNION ALL
  SELECT * FROM refund_sample
  UNION ALL
  SELECT * FROM typical_sample
),
final AS (
  SELECT
    s.payment_id,
    o.order_number,
    t.name AS merchant_name,
    s.currency_code,
    s.payment_amount,
    s.amount_refunded,
    (s.payment_amount - s.amount_refunded) AS net_amount,
    s.payout_item_amount,
    s.payout_item_fee_amount,
    (s.payout_item_amount - s.payout_item_fee_amount) AS payout_net_amount,
    (COALESCE(s.ledger_debit_total,0) - COALESCE(s.ledger_credit_total,0)) AS ledger_debit_credit_diff,
    s.ledger_credit_total,
    CASE
      WHEN s.payout_item_amount IS NULL THEN 'PENDING PAYOUT'
      WHEN (s.payment_amount - s.amount_refunded) = s.payout_item_amount
           AND (COALESCE(s.ledger_debit_total,0) - COALESCE(s.ledger_credit_total,0)) = 0
        THEN 'OK'
      ELSE 'CHECK'
    END AS reconciliation_flag,
    s.sample_category
  FROM all_samples s
  JOIN orders o ON o.id = s.order_id
  JOIN tenants t ON t.id = s.tenant_id
)
SELECT
  order_number,
  merchant_name,
  currency_code,
  payment_amount,
  amount_refunded,
  net_amount,
  payout_item_amount,
  payout_item_fee_amount,
  payout_net_amount,
  ledger_debit_credit_diff,
  ledger_credit_total,
  reconciliation_flag
FROM final
ORDER BY
  CASE sample_category WHEN 'A_LARGEST' THEN 1 WHEN 'B_REFUND' THEN 2 ELSE 3 END,
  payment_amount DESC,
  payment_id
    • The warehouse answers
      STATUS: COMPILES (dry run on the empty schema, no data read)
COLUMNS: order_number, merchant_name, currency_code, payment_amount, amount_refunded, net_amount, payout_item_amount, payout_item_fee_amount, payout_net_amount, ledger_debit_credit_diff, ledger_credit_total, reconciliation_flag
    • GraceQuery compiles and returns exactly the 12 requested columns. Submitting.
    • Grace calls submit
      WITH base_payments AS (
  SELECT
    p.id AS payment_id,
    p.tenant_id,
    p.order_id,
    p.currency_code,
    p.amount AS payment_amount,
    p.amount_refunded,
    p.captured_at
  FROM payments p
  WHERE p.status IN ('captured','refunded','partially_refunded')
    AND p.captured_at >= DATE '2025-01-01'
    AND p.captured_at < DATE '2026-01-01'
    AND p.order_id IS NOT NULL
),
fx_rates AS (
  SELECT quote_code, as_of, rate
  FROM exchange_rates
  WHERE base_code = 'EUR'
),
payments_with_eur AS (
  SELECT
    bp.*,
    CASE WHEN bp.currency_code = 'EUR' THEN bp.payment_amount
         ELSE bp.payment_amount / fx.rate END AS payment_amount_eur
  FROM base_payments bp
  LEFT JOIN fx_rates fx
    ON fx.quote_code = bp.currency_code
   AND fx.as_of = CAST(bp.captured_at AS date)
),
payout_agg AS (
  SELECT payment_id, amount AS payout_item_amount, fee_amount AS payout_item_fee_amount
  FROM payout_items
),
ledger_agg AS (
  SELECT
    payment_id,
    SUM(CASE WHEN direction = 'debit' THEN amount ELSE 0 END) AS ledger_debit_total,
    SUM(CASE WHEN direction = 'credit' THEN amount ELSE 0 END) AS ledger_credit_total
  FROM ledger_entries
  WHERE payment_id IS NOT NULL
  GROUP BY payment_id
),
enriched AS (
  SELECT
    pwe.payment_id,
    pwe.tenant_id,
    pwe.order_id,
    pwe.currency_code,
    pwe.payment_amount,
    pwe.amount_refunded,
    pwe.payment_amount_eur,
    pa.payout_item_amount,
    pa.payout_item_fee_amount,
    la.ledger_debit_total,
    la.ledger_credit_total
  FROM payments_with_eur pwe
  LEFT JOIN payout_agg pa ON pa.payment_id = pwe.payment_id
  LEFT JOIN ledger_agg la ON la.payment_id = pwe.payment_id
),
tenant_top_payment AS (
  SELECT e.*, ROW_NUMBER() OVER (PARTITION BY e.tenant_id ORDER BY e.payment_amount_eur DESC) AS tenant_rn
  FROM enriched e
),
largest_sample AS (
  SELECT
    payment_id, tenant_id, order_id, currency_code, payment_amount, amount_refunded,
    payment_amount_eur, payout_item_amount, payout_item_fee_amount,
    ledger_debit_total, ledger_credit_total, 'A_LARGEST' AS sample_category
  FROM tenant_top_payment
  WHERE tenant_rn = 1
  ORDER BY payment_amount_eur DESC
  LIMIT 8
),
refund_candidates AS (
  SELECT
    e.*,
    CASE WHEN e.amount_refunded = e.payment_amount THEN 'FULL' ELSE 'PARTIAL' END AS refund_kind
  FROM enriched e
  WHERE e.amount_refunded > 0
),
refund_ranked AS (
  SELECT
    rc.*,
    ROW_NUMBER() OVER (PARTITION BY rc.tenant_id, rc.refund_kind ORDER BY rc.amount_refunded DESC) AS tenant_refund_rn
  FROM refund_candidates rc
),
refund_sample AS (
  (SELECT payment_id, tenant_id, order_id, currency_code, payment_amount, amount_refunded,
          payment_amount_eur, payout_item_amount, payout_item_fee_amount,
          ledger_debit_total, ledger_credit_total, 'B_REFUND' AS sample_category
   FROM refund_ranked WHERE refund_kind = 'FULL' AND tenant_refund_rn = 1
   ORDER BY amount_refunded DESC LIMIT 4)
  UNION ALL
  (SELECT payment_id, tenant_id, order_id, currency_code, payment_amount, amount_refunded,
          payment_amount_eur, payout_item_amount, payout_item_fee_amount,
          ledger_debit_total, ledger_credit_total, 'B_REFUND' AS sample_category
   FROM refund_ranked WHERE refund_kind = 'PARTIAL' AND tenant_refund_rn = 1
   ORDER BY amount_refunded DESC LIMIT 4)
),
tiled AS (
  SELECT e.*, NTILE(9) OVER (ORDER BY e.payment_id) AS tile
  FROM enriched e
),
tiled_ranked AS (
  SELECT
    t.*,
    ROW_NUMBER() OVER (PARTITION BY t.tile ORDER BY (t.payout_item_amount IS NULL) DESC, t.payment_id) AS tile_rn
  FROM tiled t
),
typical_sample AS (
  SELECT
    payment_id, tenant_id, order_id, currency_code, payment_amount, amount_refunded,
    payment_amount_eur, payout_item_amount, payout_item_fee_amount,
    ledger_debit_total, ledger_credit_total, 'C_TYPICAL' AS sample_category
  FROM tiled_ranked
  WHERE tile_rn = 1
),
all_samples AS (
  SELECT * FROM largest_sample
  UNION ALL
  SELECT * FROM refund_sample
  UNION ALL
  SELECT * FROM typical_sample
),
final AS (
  SELECT
    s.payment_id,
    o.order_number,
    t.name AS merchant_name,
    s.currency_code,
    s.payment_amount,
    s.amount_refunded,
    (s.payment_amount - s.amount_refunded) AS net_amount,
    s.payout_item_amount,
    s.payout_item_fee_amount,
    (s.payout_item_amount - s.payout_item_fee_amount) AS payout_net_amount,
    (COALESCE(s.ledger_debit_total,0) - COALESCE(s.ledger_credit_total,0)) AS ledger_debit_credit_diff,
    s.ledger_credit_total,
    CASE
      WHEN s.payout_item_amount IS NULL THEN 'PENDING PAYOUT'
      WHEN (s.payment_amount - s.amount_refunded) = s.payout_item_amount
           AND (COALESCE(s.ledger_debit_total,0) - COALESCE(s.ledger_credit_total,0)) = 0
        THEN 'OK'
      ELSE 'CHECK'
    END AS reconciliation_flag,
    s.sample_category
  FROM all_samples s
  JOIN orders o ON o.id = s.order_id
  JOIN tenants t ON t.id = s.tenant_id
)
SELECT
  order_number,
  merchant_name,
  currency_code,
  payment_amount,
  amount_refunded,
  net_amount,
  payout_item_amount,
  payout_item_fee_amount,
  payout_net_amount,
  ledger_debit_credit_diff,
  ledger_credit_total,
  reconciliation_flag
FROM final
ORDER BY
  CASE sample_category WHEN 'A_LARGEST' THEN 1 WHEN 'B_REFUND' THEN 2 ELSE 3 END,
  payment_amount DESC,
  payment_id
    • The warehouse answers
      Submitted to tonight's batch. Your work on this request is done.
    • GraceSubmitted. Summary of the approach: - **Base set**: `payments` with status in (captured/refunded/partially_refunded), `captured_at` in 2025, and a linked order (needed for `order_number`). - **Enrichment**: left-joined `payout_items` (1:1 by payment) and `ledger_entries` (aggregated debit/credit totals per payment), plus an EUR-converted amount via `exchange_rates` used only for ranking. - **Sampling**: - *A — Largest (8 rows)*: each tenant's single biggest 2025 payment (EUR-ranked), then the top 8 tenants — guarantees tenant spread. - *B — Refunds (8 rows)*: top 4 tenants by largest fully-refunded payment + top 4 by largest partially-refunded payment. - *C — Typical (9 rows)*: `NTILE(9)` over `payments.id` as the deterministic pseudo-random split, preferring unmatched-payout rows within each tile when present. - **Reconciliation**: `PENDING PAYOUT` when no payout_items row exists yet; `OK` when net amount matches the settled payout amount and ledger debits/credits balance to zero; `CHECK` otherwise. - All monetary columns stay in each payment's native `currency_code` as requested, so the diff/flag checks are exact rather than FX-rounded. One caveat noted to the analyst: the "at least 2 unmatched-payout" condition in category C is favored by the tiling logic but isn't a hard guarantee if payouts happen to cover every tile.

    Not shown here: 239 KB of context the agent was given, its instructions and the schema documentation; it is in the raw transcript.

    Grace's transcript (306 KB) · Kofi Mensah's transcript (906 KB) · Tobias Lindqvist's transcript (269 KB) · the night's plan (7 KB) · the night's reports (14 KB) · the week's memo (3 KB)