pool stats migration checks

Author: Cmdv

cardano-db/src/Cardano/Db/Operations/Delete.hs

@@ -127,7 +127,7 @@ deleteUsingEpochNo epochN = do
         [ onlyDelete "Epoch" [EpochNo ==. epochN]
         , onlyDelete "DrepDistr" [DrepDistrEpochNo >. epochN]
         , onlyDelete "RewardRest" [RewardRestSpendableEpoch >. epochN]
-        , onlyDelete "PoolStat" [PoolStatEpochNo >=. epochN]
+        , onlyDelete "PoolStat" [PoolStatEpochNo >. epochN]
         ]
   nullLogs <- do
     a <- setNullEnacted epochN

schema/migration-2-0045-20252107.sql

@@ -0,0 +1,35 @@
+CREATE FUNCTION migrate() RETURNS void AS $$
+DECLARE
+  next_version int ;
+BEGIN
+  SELECT stage_two + 1 INTO next_version FROM schema_version ;
+  IF next_version = 45 THEN
+
+    -- Remove duplicates first
+    DELETE FROM pool_stat
+    WHERE id NOT IN (
+      SELECT DISTINCT ON (pool_hash_id, epoch_no) id
+      FROM pool_stat
+      ORDER BY pool_hash_id, epoch_no, id
+    );
+
+    -- Then add constraint if it doesn't exist
+    DO $$
+    BEGIN
+      IF NOT EXISTS (
+        SELECT 1 FROM pg_constraint
+        WHERE conname = 'unique_pool_stat_epoch'
+      ) THEN
+        ALTER TABLE "pool_stat" ADD CONSTRAINT "unique_pool_stat_epoch"
+        UNIQUE ("pool_hash_id", "epoch_no");
+      END IF;
+    END $$;
+
+    UPDATE schema_version SET stage_two = next_version ;
+    RAISE NOTICE 'DB has been migrated to stage_two version %', next_version ;
+  END IF ;
+END ;
+$$ LANGUAGE plpgsql ;
+
+SELECT migrate() ;
+DROP FUNCTION migrate() ;