From 9d6e71f327ba170f662574d29bde9a82f4e92202 Mon Sep 17 00:00:00 2001
From: Justin Gasper <jmgasper@gmail.com>
Date: Wed, 25 Feb 2026 17:41:15 +1100
Subject: [PATCH] Optimization for registrants history report

---
 .../challenges/registrants-history.sql        | 117 ++++++++++++------
 1 file changed, 78 insertions(+), 39 deletions(-)

diff --git a/sql/reports/challenges/registrants-history.sql b/sql/reports/challenges/registrants-history.sql
index 943e6c5..bad5bb2 100644
--- a/sql/reports/challenges/registrants-history.sql
+++ b/sql/reports/challenges/registrants-history.sql
@@ -1,47 +1,86 @@
+WITH submitter_role AS (
+  SELECT rr.id
+  FROM resources."ResourceRole" rr
+  WHERE rr."nameLower" = 'submitter'
+  LIMIT 1
+),
+filtered_challenges AS (
+  SELECT
+    c.id,
+    c.status,
+    latest_phase."actualEndDate" as "challengeCompletedDate"
+  FROM
+    challenges."Challenge" c
+  LEFT JOIN LATERAL (
+    SELECT cp."actualEndDate"
+    FROM challenges."ChallengePhase" cp
+    WHERE cp."challengeId" = c.id
+    ORDER BY cp."scheduledEndDate" DESC
+    LIMIT 1
+  ) latest_phase ON true
+  WHERE
+    -- filter by billing account
+    (
+      $1::text[] IS NULL
+      OR EXISTS (
+        SELECT 1
+        FROM challenges."ChallengeBilling" cb
+        WHERE cb."challengeId" = c.id
+          AND cb."billingAccountId" = ANY($1::text[])
+      )
+    )
+    -- filter by excluding billing account
+    AND (
+      $2::text[] IS NULL
+      OR NOT EXISTS (
+        SELECT 1
+        FROM challenges."ChallengeBilling" cb
+        WHERE cb."challengeId" = c.id
+          AND cb."billingAccountId" = ANY($2::text[])
+      )
+    )
+    -- filter by challenge status
+    AND ($3::text[] IS NULL OR c.status::text = ANY($3::text[]))
+    -- filter by completion date bounds on the latest challenge phase end date
+    AND (
+      ($4::timestamptz IS NULL AND $5::timestamptz IS NULL)
+      OR (
+        latest_phase."actualEndDate" IS NOT NULL
+        AND ($4::timestamptz IS NULL OR latest_phase."actualEndDate" >= $4::timestamptz)
+        AND ($5::timestamptz IS NULL OR latest_phase."actualEndDate" <= $5::timestamptz)
+      )
+    )
+)
 SELECT
-  c.id as "challengeId",
-  c.status as "challengeStatus",
+  registrants."challengeId",
+  registrants."challengeStatus",
   cw.handle as "winnerHandle",
   CASE WHEN sub.placement = 1 THEN true ELSE false END as "isWinner",
   CASE
-    WHEN c.status = 'COMPLETED' THEN latest_phase."actualEndDate"
+    WHEN registrants."challengeStatus" = 'COMPLETED'
+      THEN registrants."challengeCompletedDate"
     ELSE null
   END as "challengeCompletedDate",
-  res."memberHandle" as "registrantHandle",
+  registrants."registrantHandle",
   ROUND(sub."finalScore", 2) as "registrantFinalScore"
-FROM
-  challenges."Challenge" c
-LEFT JOIN LATERAL (
-  SELECT cp."actualEndDate"
-  FROM challenges."ChallengePhase" cp
-  WHERE cp."challengeId" = c.id
-  ORDER BY cp."scheduledEndDate" DESC
-  LIMIT 1
-) latest_phase ON true
-LEFT JOIN
-  resources."Resource" res ON c.id = res."challengeId"
-LEFT JOIN
-  resources."ResourceRole" rr on res."roleId" = rr.id
-LEFT JOIN
-  challenges."ChallengeWinner" cw ON c.id = cw."challengeId" AND cw."userId"::text=res."memberId"
-LEFT JOIN
-  reviews."submission" sub on sub."memberId"=res."memberId" AND sub."challengeId"=c.id
-LEFT JOIN
-  challenges."ChallengeBilling" cb on cb."challengeId"=c.id
-WHERE rr.name = 'Submitter'
-  -- filter by billing account
-  AND ($1::text[] IS NULL OR cb."billingAccountId" = ANY($1::text[]))
-  -- filter by excluding billing account
-  AND ($2::text[] IS NULL OR cb."billingAccountId" <> ANY($2::text[]))
-  -- filter by challenge status
-  AND ($3::text[] IS NULL OR c.status::text= ANY($3::text[]))
-  -- filter by completion date bounds on the latest challenge phase end date
-  AND (
-    ($4::timestamptz IS NULL AND $5::timestamptz IS NULL)
-    OR (
-      latest_phase."actualEndDate" IS NOT NULL
-      AND ($4::timestamptz IS NULL OR latest_phase."actualEndDate" >= $4::timestamptz)
-      AND ($5::timestamptz IS NULL OR latest_phase."actualEndDate" <= $5::timestamptz)
-    )
-  )
+FROM (
+  SELECT
+    fc.id as "challengeId",
+    fc.status as "challengeStatus",
+    fc."challengeCompletedDate",
+    res."memberId",
+    res."memberHandle" as "registrantHandle"
+  FROM filtered_challenges fc
+  JOIN submitter_role sr ON true
+  JOIN resources."Resource" res
+    ON res."challengeId" = fc.id
+    AND res."roleId" = sr.id
+  LIMIT 1000
+) registrants
+LEFT JOIN challenges."ChallengeWinner" cw
+  ON cw."challengeId" = registrants."challengeId"
+  AND cw."userId"::text = registrants."memberId"
+LEFT JOIN reviews."submission" sub
+  ON sub."challengeId" = registrants."challengeId"
+  AND sub."memberId" = registrants."memberId"
 LIMIT 1000;