DB Olympics

Queries · q042 · VP Customer Experience · week 1, night 2

Returns and refunds: volume and time-to-resolve trend

“How often do shoppers end up requesting a return/refund, and how long does that process take to resolve, and is it changing over time?”

Manager · asked the questionDaniel AchterbergVP Customer Experience. Former head of support at a marketplace. Merchants run their helpdesk on Tidewick, so their shoppers' experience is partly Tidewick's reputation.
Analyst · planned the reportMateo RuizComparative: likes year-over-year and peer comparisons across merchants and countries.
Engineer · wrote the SQLFelixJunior engineer who nests subqueries in FROM and WHERE (IN, EXISTS, correlated subqueries) rather than CTEs.

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

  1. Daniel Achterberg writes to Mateo Ruiz

    The manager, at the start of week 1

    Subject: Where I'd like to start — support & shopper experience

    Hi Mateo,

    Good to have you on this with me. I'm still building my map of the business, so I want to keep this week broad — I'd rather get a solid first read on a few big questions than a deep dive on one. Here's what's on my mind, roughly in priority order:

    1. How are we doing on response and resolution times, and is it getting better or worse? I keep hearing "we're slow" anecdotally but have no sense of the trend, or whether it varies a lot by merchant. I need a baseline I can put in front of the leadership team.
    2. Where is the support load actually coming from? What kinds of problems are shoppers contacting merchants about most, and has that mix been shifting lately? I want to know if there's a theme we could fix at the platform level instead of merchant-by-merchant.
    3. What does the returns and refunds experience look like from the shopper's side? How often shoppers end up wanting their money back, how long that takes to resolve, and whether that's a smooth process or a source of frustration. This feels close to our reputation.
    4. How satisfied are shoppers overall, and where is satisfaction weakest? I'd like a sense of satisfaction levels and whether certain merchants or situations stand out as problem spots.
    5. (If there's room this week) What are reviews and ratings telling us? Even a first look at how shoppers rate their purchases, and whether that lines up with what we see in support, would help me understand if there are blind spots in the ticket data.

    What I need these for: I'm meeting merchant success and the exec team soon and want a credible, numbers-backed view of shopper experience — not just war stories. I also want to start spotting the two or three things that, if we fixed them, would move the needle most broadly across merchants, rather than chasing individual complaints.

    Given the slot constraints, let's prioritize #1 through #3 this week if we can't fit all five — those feel most urgent to me. Happy to talk through any of this before you lock in requests.

    Thanks, Daniel

  2. Mateo Ruiz plans the night

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

    Reading report 1: year-end (Nov/Dec) spikes in volume, response and resolution time repeat every year (2023, 2024, 2025) — that looks like seasonal/holiday load and is somewhat expected, though worth noting for the memo. What's NOT seasonal is the 2025-05/2025-06 spike (resolution hours jump to 52.7/87.2, response to 26.5/45.1, breach rate to 36.9/45.6%) — nothing comparable appears in 2023 or 2024 mid-year, so I want to find the cause rather than assume it's noise. Report 3 shows delivery + where-is-my-order tags are already >65% of tagged tickets in the last 6 months and growing share while complaint/return/product-question shrink in share — that's the platform-level theme Daniel asked about in priority #2, and it may also explain the resolution-time trend in #1 if delivery tickets take longer to resolve and are concentrated in the spike months. Tonight I'm chasing both of these (merchant concentration of the May-Jun spike, and whether delivery-tagged tickets specifically explain slow/volatile resolution times), plus opening priority #3 (returns/refunds) with a foundational trend report so we have something in hand for that question this week. I don't need a new slot for a plain YoY same-month pivot — I can build that directly off report 1's numbers for the memo.

    Returns and refunds: volume and time-to-resolve trend
    Question
    How often do shoppers end up requesting a return/refund, and how long does that process take to resolve, and is it changing over time?
    One row per
    one calendar month, platform-wide
    Columns
    • month (YYYY-MM)
    • orders placed
    • returns requested
    • return rate (%)
    • returns refunded (count)
    • avg days requested-to-refunded
    • median days requested-to-refunded
    • returns rejected (%)
  3. Felix writes the SQL

    The engineer · 2 dry runs on the empty schema, then the submission

    Dry run 1 · STATUS: REJECTED
    SELECT
      COALESCE(om.month, rm.month) AS month,
      om.orders_placed,
      rm.returns_requested,
      CASE WHEN om.orders_placed > 0 THEN ROUND(rm.returns_requested * 100.0 / om.orders_placed, 1) ELSE NULL END AS return_rate_pct,
      rm.returns_refunded,
      rm.avg_days_requested_to_refunded,
      rm.median_days_requested_to_refunded,
      CASE WHEN rm.returns_requested > 0 THEN ROUND(rm.returns_rejected * 100.0 / rm.returns_requested, 1) ELSE NULL END AS returns_rejected_pct
    FROM
      (SELECT to_char(date_trunc('month', placed_at), 'YYYY-MM') AS month, count(*) AS orders_placed
       FROM orders
       WHERE placed_at >= DATE '2023-01-01' AND placed_at < DATE '2026-01-01'
       GROUP BY 1) om
    FULL OUTER JOIN
      (SELECT to_char(date_trunc('month', requested_at), 'YYYY-MM') AS month,
              count(*) AS returns_requested,
              count(*) FILTER (WHERE status = 'refunded') AS returns_refunded,
              count(*) FILTER (WHERE status = 'rejected') AS returns_rejected,
              ROUND(AVG(extract(epoch from (refunded_at - requested_at))/86400) FILTER (WHERE status = 'refunded' AND refunded_at IS NOT NULL), 1) AS avg_days_requested_to_refunded,
              ROUND(CAST(percentile_cont(0.5) WITHIN GROUP (ORDER BY extract(epoch from (refunded_at - requested_at))/86400) FILTER (WHERE status = 'refunded' AND refunded_at IS NOT NULL) AS numeric), 1) AS median_days_requested_to_refunded
       FROM order_returns
       WHERE requested_at >= DATE '2023-01-01' AND requested_at < DATE '2026-01-01'
       GROUP BY 1) rm
    ON om.month = rm.month
    ORDER BY COALESCE(om.month, rm.month)
    Dry run 2 · 2 changes from the dry run before · STATUS: COMPILES (dry run on the empty schema, no data read)
    SELECT  COALESCE(om.month, rm.month) AS month,  om.orders_placed,  rm.returns_requested,  CASE WHEN om.orders_placed > 0 THEN ROUND(rm.returns_requested * 100.0 / om.orders_placed, 1) ELSE NULL END AS return_rate_pct,  rm.returns_refunded,  rm.avg_days_requested_to_refunded,  rm.median_days_requested_to_refunded,  CASE WHEN rm.returns_requested > 0 THEN ROUND(rm.returns_rejected * 100.0 / rm.returns_requested, 1) ELSE NULL END AS returns_rejected_pctFROM  (SELECT to_char(date_trunc('month', placed_at), 'YYYY-MM') AS month, count(*) AS orders_placed  (SELECT strftime(date_trunc('month', placed_at), '%Y-%m') AS month, count(*) AS orders_placed   FROM orders   WHERE placed_at >= DATE '2023-01-01' AND placed_at < DATE '2026-01-01'   GROUP BY 1) omFULL OUTER JOIN  (SELECT to_char(date_trunc('month', requested_at), 'YYYY-MM') AS month,  (SELECT strftime(date_trunc('month', requested_at), '%Y-%m') AS month,          count(*) AS returns_requested,          count(*) FILTER (WHERE status = 'refunded') AS returns_refunded,          count(*) FILTER (WHERE status = 'rejected') AS returns_rejected,          ROUND(AVG(extract(epoch from (refunded_at - requested_at))/86400) FILTER (WHERE status = 'refunded' AND refunded_at IS NOT NULL), 1) AS avg_days_requested_to_refunded,          ROUND(CAST(percentile_cont(0.5) WITHIN GROUP (ORDER BY extract(epoch from (refunded_at - requested_at))/86400) FILTER (WHERE status = 'refunded' AND refunded_at IS NOT NULL) AS numeric), 1) AS median_days_requested_to_refunded   FROM order_returns   WHERE requested_at >= DATE '2023-01-01' AND requested_at < DATE '2026-01-01'   GROUP BY 1) rmON om.month = rm.monthORDER BY COALESCE(om.month, rm.month)

    “Query compiles with the expected 8 columns. Submitting.”

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

    “Submitted. The report gives one row per month (2023-01 through 2025-12) with orders placed, returns requested, the approximate return rate, refunded-return counts, average/median days from request to refund, and the rejection rate — built as independent monthly aggregates over orders and order_returns, joined on month.”

  4. The report comes back overnight

    As Mateo Ruiz saw it, from the small dataset the agents worked on

    month   | orders_placed | returns_requested | return_rate_pct | returns_refunded | avg_days_requested_to_refunded | median_days_requested_to_refunded | returns_rejected_pct
    --------+---------------+-------------------+-----------------+------------------+--------------------------------+-----------------------------------+---------------------
    2023-01 |           518 |                53 |            10.2 |               51 |                            8.7 |                               8.7 |                  3.8
    2023-02 |           546 |                90 |            16.5 |               88 |                            8.6 |                               8.8 |                  2.2
    2023-03 |           638 |               120 |            18.8 |              116 |                            8.0 |                               7.8 |                  3.3
    2023-04 |           677 |               133 |            19.6 |              131 |                            7.8 |                               7.7 |                  1.5
    2023-05 |           804 |               104 |            12.9 |              102 |                            8.0 |                               8.1 |                  1.9
    2023-06 |           746 |               124 |            16.6 |              120 |                            8.0 |                               7.9 |                  3.2
    2023-07 |           789 |               138 |            17.5 |              131 |                            7.7 |                               7.8 |                  5.1
    2023-08 |           842 |               123 |            14.6 |              118 |                            7.7 |                               7.6 |                  4.1
    2023-09 |           902 |               136 |            15.1 |              134 |                            7.5 |                               7.5 |                  1.5
    2023-10 |          1081 |               139 |            12.9 |              132 |                            7.8 |                               7.9 |                  5.0
    2023-11 |          1845 |               214 |            11.6 |              203 |                            8.1 |                               8.0 |                  5.1
    2023-12 |          1605 |               491 |            30.6 |              460 |                            7.9 |                               7.7 |                  6.3
    2024-01 |          1324 |               262 |            19.8 |              250 |                            7.8 |                               7.7 |                  4.6
    2024-02 |          1108 |               165 |            14.9 |              156 |                            8.3 |                               8.5 |                  5.5
    2024-03 |          1201 |               143 |            11.9 |              136 |                            8.0 |                               7.9 |                  4.9
    2024-04 |          1238 |               173 |            14.0 |              169 |                            8.3 |                               8.4 |                  2.3
    2024-05 |          1356 |               190 |            14.0 |              178 |                            7.9 |                               7.8 |                  6.3
    2024-06 |          1307 |               193 |            14.8 |              186 |                            7.8 |                               7.7 |                  3.6
    2024-07 |          1377 |               233 |            16.9 |              227 |                            7.9 |                               8.2 |                  2.6
    2024-08 |          1316 |               204 |            15.5 |              191 |                            8.0 |                               7.9 |                  6.4
    2024-09 |          1353 |               192 |            14.2 |              181 |                            8.0 |                               8.0 |                  5.7
    2024-10 |          1499 |               196 |            13.1 |              185 |                            7.7 |                               7.6 |                  5.6
    2024-11 |          2130 |               267 |            12.5 |              260 |                            7.8 |                               7.8 |                  2.6
    2024-12 |          2644 |               643 |            24.3 |              615 |                            7.9 |                               7.9 |                  4.4
    2025-01 |          1827 |               349 |            19.1 |              337 |                            7.8 |                               7.7 |                  3.4
    2025-02 |          1400 |               176 |            12.6 |              170 |                            7.7 |                               7.6 |                  3.4
    2025-03 |          1638 |               187 |            11.4 |              177 |                            7.8 |                               7.9 |                  5.3
    2025-04 |          1568 |               230 |            14.7 |              217 |                            7.7 |                               7.6 |                  5.7
    2025-05 |          1691 |               252 |            14.9 |              244 |                            7.9 |                               7.9 |                  3.2
    2025-06 |          1509 |               254 |            16.8 |              243 |                            7.8 |                               7.8 |                  4.3
    2025-07 |          1648 |               243 |            14.7 |              231 |                            7.8 |                               8.0 |                  4.9
    2025-08 |          1564 |               217 |            13.9 |              209 |                            8.0 |                               8.2 |                  3.7
    2025-09 |          1712 |               252 |            14.7 |              238 |                            7.6 |                               7.6 |                  5.6
    2025-10 |          1879 |               270 |            14.4 |              257 |                            7.9 |                               7.8 |                  4.8
    2025-11 |          2645 |               331 |            12.5 |              318 |                            8.0 |                               8.0 |                  3.9
    2025-12 |          3112 |               702 |            22.6 |              524 |                            7.7 |                               7.6 |                  3.3
    (36 rows)
  5. What came of it

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

    Later queries that build on this report:

  6. It becomes benchmark query q042

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

    • placeholderyear month (2×)
    • numericsdocs/NUMERICS.md: rounding removed; results keep full precision
    • numericsdocs/NUMERICS.md: rounding removed; results keep full precision
    • numericsdocs/NUMERICS.md: rounding removed; results keep full precision; bare NUMERIC cast that only served the rounding removed
    • numericsdocs/NUMERICS.md: EXTRACT(EPOCH FROM (b - a)) cast to NUMERIC(18,6) (2×)
    • made explicita selected t.col gets AS col, its standard name made explicit (5×)
    • placeholderpercentile cont
    • placeholderseconds between (2×)
    • determinismthe standard leaves the place of NULLs in a sort to the implementation: NULLS LAST ascending, NULLS FIRST descending, as in the reference results
    The benchmark text, against the submitted SQL
    SELECT  COALESCE(om.month, rm.month) AS month,  om.orders_placed,  rm.returns_requested,  CASE WHEN om.orders_placed > 0 THEN ROUND(rm.returns_requested * 100.0 / om.orders_placed, 1) ELSE NULL END AS return_rate_pct,  rm.returns_refunded,  rm.avg_days_requested_to_refunded,  rm.median_days_requested_to_refunded,  CASE WHEN rm.returns_requested > 0 THEN ROUND(rm.returns_rejected * 100.0 / rm.returns_requested, 1) ELSE NULL END AS returns_rejected_pct  om.orders_placed AS orders_placed,  rm.returns_requested AS returns_requested,  CASE WHEN om.orders_placed > 0 THEN rm.returns_requested * 100.0 / om.orders_placed ELSE NULL END AS return_rate_pct,  rm.returns_refunded AS returns_refunded,  rm.avg_days_requested_to_refunded AS avg_days_requested_to_refunded,  rm.median_days_requested_to_refunded AS median_days_requested_to_refunded,  CASE WHEN rm.returns_requested > 0 THEN rm.returns_rejected * 100.0 / rm.returns_requested ELSE NULL END AS returns_rejected_pctFROM  (SELECT strftime(date_trunc('month', placed_at), '%Y-%m') AS month, count(*) AS orders_placed  (SELECT {{year_month(date_trunc('month', placed_at))}} AS month, count(*) AS orders_placed   FROM orders   WHERE placed_at >= DATE '2023-01-01' AND placed_at < DATE '2026-01-01'   GROUP BY 1) omFULL OUTER JOIN  (SELECT strftime(date_trunc('month', requested_at), '%Y-%m') AS month,  (SELECT {{year_month(date_trunc('month', requested_at))}} AS month,          count(*) AS returns_requested,          count(*) FILTER (WHERE status = 'refunded') AS returns_refunded,          count(*) FILTER (WHERE status = 'rejected') AS returns_rejected,          ROUND(AVG(extract(epoch from (refunded_at - requested_at))/86400) FILTER (WHERE status = 'refunded' AND refunded_at IS NOT NULL), 1) AS avg_days_requested_to_refunded,          ROUND(CAST(percentile_cont(0.5) WITHIN GROUP (ORDER BY extract(epoch from (refunded_at - requested_at))/86400) FILTER (WHERE status = 'refunded' AND refunded_at IS NOT NULL) AS numeric), 1) AS median_days_requested_to_refunded          AVG({{seconds_between(requested_at, refunded_at)}}/86400) FILTER (WHERE status = 'refunded' AND refunded_at IS NOT NULL) AS avg_days_requested_to_refunded,          {{percentile_cont_filter(0.5, {{seconds_between(requested_at, refunded_at)}}/86400, status = 'refunded' AND refunded_at IS NOT NULL)}} AS median_days_requested_to_refunded   FROM order_returns   WHERE requested_at >= DATE '2023-01-01' AND requested_at < DATE '2026-01-01'   GROUP BY 1) rmON om.month = rm.monthORDER BY COALESCE(om.month, rm.month)ORDER BY COALESCE(om.month, rm.month) NULLS LAST
    SELECT
      COALESCE(om.month, rm.month) AS month,
      om.orders_placed AS orders_placed,
      rm.returns_requested AS returns_requested,
      CASE WHEN om.orders_placed > 0 THEN rm.returns_requested * 100.0 / om.orders_placed ELSE NULL END AS return_rate_pct,
      rm.returns_refunded AS returns_refunded,
      rm.avg_days_requested_to_refunded AS avg_days_requested_to_refunded,
      rm.median_days_requested_to_refunded AS median_days_requested_to_refunded,
      CASE WHEN rm.returns_requested > 0 THEN rm.returns_rejected * 100.0 / rm.returns_requested ELSE NULL END AS returns_rejected_pct
    FROM
      (SELECT strftime(date_trunc('month', placed_at), '%Y-%m') AS month, count(*) AS orders_placed
       FROM orders
       WHERE placed_at >= DATE '2023-01-01' AND placed_at < DATE '2026-01-01'
       GROUP BY 1) om
    FULL OUTER JOIN
      (SELECT strftime(date_trunc('month', requested_at), '%Y-%m') AS month,
              count(*) AS returns_requested,
              count(*) FILTER (WHERE status = 'refunded') AS returns_refunded,
              count(*) FILTER (WHERE status = 'rejected') AS returns_rejected,
              AVG(CAST(EXTRACT(EPOCH FROM (refunded_at - requested_at)) AS NUMERIC(18,6))/86400) FILTER (WHERE status = 'refunded' AND refunded_at IS NOT NULL) AS avg_days_requested_to_refunded,
              PERCENTILE_CONT(0.5) WITHIN GROUP (ORDER BY CAST(EXTRACT(EPOCH FROM (refunded_at - requested_at)) AS NUMERIC(18,6))/86400) FILTER (WHERE status = 'refunded' AND refunded_at IS NOT NULL) AS median_days_requested_to_refunded
       FROM order_returns
       WHERE requested_at >= DATE '2023-01-01' AND requested_at < DATE '2026-01-01'
       GROUP BY 1) rm
    ON om.month = rm.month
    ORDER BY COALESCE(om.month, rm.month) NULLS LAST
    10 ms100 ms1 sHyper115 msDuckDB115 msGizmoSQL110 msclickhouse_brew119 msFirebolt91.9 msDataFusionwrong resultClickHouse323 ms
    • DataFusionrow count 36 vs 1
  7. 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

    Felix's whole session, 9 turns
    • The request, as Felix received it
      Report request from Mateo Ruiz (analyst for the VP Customer Experience):
      
      Title: Returns and refunds: volume and time-to-resolve trend
      Question: How often do shoppers end up requesting a return/refund, and how long does that process take to resolve, and is it changing over time?
      Grain: one calendar month, platform-wide
      Columns:
      - month (YYYY-MM)
      - orders placed
      - returns requested
      - return rate (%)
      - returns refunded (count)
      - avg days requested-to-refunded
      - median days requested-to-refunded
      - returns rejected (%)
      Details: Source: order_returns (for request/approval/refund lifecycle) and orders (for volume denominator). Grain the month on order_returns.requested_at for return-side columns, and on orders.placed_at for 'orders placed'. Return rate = returns requested that month / orders placed that same month, as a percentage rounded to 1 decimal -- note in the report that this is an approximation since a return in month M may relate to an order placed in an earlier month, not necessarily the same month's orders. 'avg/median days requested-to-refunded' = extract(epoch from refunded_at - requested_at)/86400, averaged/median over returns in that month with status='refunded' and refunded_at not null. 'returns rejected (%)' = count of order_returns with status='rejected' that month / total returns requested that month, as a percentage rounded to 1 decimal. Window: 2023-01-01 through 2025-12-31 (36 months). Round day figures to 1 decimal. Order by month ascending.
      
      Check your query with the warehouse's dry_run tool, then hand it in with submit.
    • Felix calls dry_run
      SELECT
        COALESCE(om.month, rm.month) AS month,
        om.orders_placed,
        rm.returns_requested,
        CASE WHEN om.orders_placed > 0 THEN ROUND(rm.returns_requested * 100.0 / om.orders_placed, 1) ELSE NULL END AS return_rate_pct,
        rm.returns_refunded,
        rm.avg_days_requested_to_refunded,
        rm.median_days_requested_to_refunded,
        CASE WHEN rm.returns_requested > 0 THEN ROUND(rm.returns_rejected * 100.0 / rm.returns_requested, 1) ELSE NULL END AS returns_rejected_pct
      FROM
        (SELECT to_char(date_trunc('month', placed_at), 'YYYY-MM') AS month, count(*) AS orders_placed
         FROM orders
         WHERE placed_at >= DATE '2023-01-01' AND placed_at < DATE '2026-01-01'
         GROUP BY 1) om
      FULL OUTER JOIN
        (SELECT to_char(date_trunc('month', requested_at), 'YYYY-MM') AS month,
                count(*) AS returns_requested,
                count(*) FILTER (WHERE status = 'refunded') AS returns_refunded,
                count(*) FILTER (WHERE status = 'rejected') AS returns_rejected,
                ROUND(AVG(extract(epoch from (refunded_at - requested_at))/86400) FILTER (WHERE status = 'refunded' AND refunded_at IS NOT NULL), 1) AS avg_days_requested_to_refunded,
                ROUND(CAST(percentile_cont(0.5) WITHIN GROUP (ORDER BY extract(epoch from (refunded_at - requested_at))/86400) FILTER (WHERE status = 'refunded' AND refunded_at IS NOT NULL) AS numeric), 1) AS median_days_requested_to_refunded
         FROM order_returns
         WHERE requested_at >= DATE '2023-01-01' AND requested_at < DATE '2026-01-01'
         GROUP BY 1) rm
      ON om.month = rm.month
      ORDER BY COALESCE(om.month, rm.month)
    • The warehouse answers
      STATUS: REJECTED
        - does not compile: Catalog Error: Scalar Function with name to_char does not exist!
    • Felix calls dry_run
      SELECT
        COALESCE(om.month, rm.month) AS month,
        om.orders_placed,
        rm.returns_requested,
        CASE WHEN om.orders_placed > 0 THEN ROUND(rm.returns_requested * 100.0 / om.orders_placed, 1) ELSE NULL END AS return_rate_pct,
        rm.returns_refunded,
        rm.avg_days_requested_to_refunded,
        rm.median_days_requested_to_refunded,
        CASE WHEN rm.returns_requested > 0 THEN ROUND(rm.returns_rejected * 100.0 / rm.returns_requested, 1) ELSE NULL END AS returns_rejected_pct
      FROM
        (SELECT strftime(date_trunc('month', placed_at), '%Y-%m') AS month, count(*) AS orders_placed
         FROM orders
         WHERE placed_at >= DATE '2023-01-01' AND placed_at < DATE '2026-01-01'
         GROUP BY 1) om
      FULL OUTER JOIN
        (SELECT strftime(date_trunc('month', requested_at), '%Y-%m') AS month,
                count(*) AS returns_requested,
                count(*) FILTER (WHERE status = 'refunded') AS returns_refunded,
                count(*) FILTER (WHERE status = 'rejected') AS returns_rejected,
                ROUND(AVG(extract(epoch from (refunded_at - requested_at))/86400) FILTER (WHERE status = 'refunded' AND refunded_at IS NOT NULL), 1) AS avg_days_requested_to_refunded,
                ROUND(CAST(percentile_cont(0.5) WITHIN GROUP (ORDER BY extract(epoch from (refunded_at - requested_at))/86400) FILTER (WHERE status = 'refunded' AND refunded_at IS NOT NULL) AS numeric), 1) AS median_days_requested_to_refunded
         FROM order_returns
         WHERE requested_at >= DATE '2023-01-01' AND requested_at < DATE '2026-01-01'
         GROUP BY 1) rm
      ON om.month = rm.month
      ORDER BY COALESCE(om.month, rm.month)
    • The warehouse answers
      STATUS: COMPILES (dry run on the empty schema, no data read)
      COLUMNS: month, orders_placed, returns_requested, return_rate_pct, returns_refunded, avg_days_requested_to_refunded, median_days_requested_to_refunded, returns_rejected_pct
    • FelixQuery compiles with the expected 8 columns. Submitting.
    • Felix calls submit
      SELECT
        COALESCE(om.month, rm.month) AS month,
        om.orders_placed,
        rm.returns_requested,
        CASE WHEN om.orders_placed > 0 THEN ROUND(rm.returns_requested * 100.0 / om.orders_placed, 1) ELSE NULL END AS return_rate_pct,
        rm.returns_refunded,
        rm.avg_days_requested_to_refunded,
        rm.median_days_requested_to_refunded,
        CASE WHEN rm.returns_requested > 0 THEN ROUND(rm.returns_rejected * 100.0 / rm.returns_requested, 1) ELSE NULL END AS returns_rejected_pct
      FROM
        (SELECT strftime(date_trunc('month', placed_at), '%Y-%m') AS month, count(*) AS orders_placed
         FROM orders
         WHERE placed_at >= DATE '2023-01-01' AND placed_at < DATE '2026-01-01'
         GROUP BY 1) om
      FULL OUTER JOIN
        (SELECT strftime(date_trunc('month', requested_at), '%Y-%m') AS month,
                count(*) AS returns_requested,
                count(*) FILTER (WHERE status = 'refunded') AS returns_refunded,
                count(*) FILTER (WHERE status = 'rejected') AS returns_rejected,
                ROUND(AVG(extract(epoch from (refunded_at - requested_at))/86400) FILTER (WHERE status = 'refunded' AND refunded_at IS NOT NULL), 1) AS avg_days_requested_to_refunded,
                ROUND(CAST(percentile_cont(0.5) WITHIN GROUP (ORDER BY extract(epoch from (refunded_at - requested_at))/86400) FILTER (WHERE status = 'refunded' AND refunded_at IS NOT NULL) AS numeric), 1) AS median_days_requested_to_refunded
         FROM order_returns
         WHERE requested_at >= DATE '2023-01-01' AND requested_at < DATE '2026-01-01'
         GROUP BY 1) rm
      ON om.month = rm.month
      ORDER BY COALESCE(om.month, rm.month)
    • The warehouse answers
      Submitted to tonight's batch. Your work on this request is done.
    • FelixSubmitted. The report gives one row per month (2023-01 through 2025-12) with orders placed, returns requested, the approximate return rate, refunded-return counts, average/median days from request to refund, and the rejection rate — built as independent monthly aggregates over `orders` and `order_returns`, joined on month.