Merge pull request #3136 from IntersectMBO/fix/3134-incorrect-delegation-amount

fix(#3134): calculating withdrawals when there are no rewards

Author: MSzalowski

CHANGELOG.md

@@ -14,13 +14,14 @@ changes.
 
 ### Fixed
 
+- Fix calculating withdrawals when rewards records are empty for a given stake key [Issue 3134](https://github.com/IntersectMBO/govtool/issues/3134)
+
 ### Changed
 
 ### Removed
 
 ## [v2.0.13](https://github.com/IntersectMBO/govtool/releases/tag/v2.0.13) 2025-02-27
 
-
 ### Added
 
 ### Fixed

govtool/backend/sql/get-stake-key-voting-power.sql

@@ -38,7 +38,15 @@ Withdrawal AS (
     w.addr_id
 )
 SELECT
-  (COALESCE(rr.amount, 0) + COALESCE(r.amount, 0) + COALESCE(b.amount, 0) - COALESCE(w.withdrawal_amount, 0)) AS total_balance,
+  (COALESCE(rr.amount, 0) + COALESCE(r.amount, 0) + COALESCE(b.amount, 0) - 
+  -- records in rewards tables might be missing for some epochs
+  -- so we need to check if the sum of rewards is greater than the sum of withdrawals before subtracting
+    CASE 
+      WHEN COALESCE(rr.amount, 0) + COALESCE(r.amount, 0) > COALESCE(w.withdrawal_amount, 0) 
+      THEN COALESCE(w.withdrawal_amount, 0) 
+      ELSE 0 
+    END
+  ) AS total_balance,
   b.addr_raw::text AS stake_address
 FROM
   Balance b