fix: 과거 가격 데이터 upsert → insert-only로 변경 (Yahoo adjusted price 덮어쓰기 방지)

과거 OHLC 행은 on_conflict_do_nothing, 오늘 행만 on_conflict_do_update.
Yahoo Finance의 배당·분할 소급 조정으로 인한 기존 PIT 데이터 훼손 방지.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/services/price_data_service.py

@@ -480,13 +480,16 @@ class PriceDataService:
                 return None
 
         now = datetime.now(timezone.utc)
-        rows = []
+        today = now.date()
+        historical_rows = []
+        live_rows = []
         for date_idx, row in hist_data.iterrows():
             price_date = date_idx.to_pydatetime()
             if price_date.tzinfo is None:
                 price_date = price_date.replace(tzinfo=timezone.utc)
 
-            rows.append({
+            target_rows = live_rows if price_date.date() >= today else historical_rows
+            target_rows.append({
                 'id': _uuid.uuid4(),
                 'ticker': ticker,
                 'date': price_date,
@@ -501,26 +504,34 @@ class PriceDataService:
                 'updated_at': now,
             })
 
-        if not rows:
+        if not historical_rows and not live_rows:
             return
 
-        # Upsert: on conflict update OHLCV + updated_at so that stale intraday-cached rows
-        # get overwritten when force_refresh=True re-fetches final EOD data.
-        stmt = pg_insert(PriceData).values(rows)
-        stmt = stmt.on_conflict_do_update(
-            constraint='uq_price_data',
-            set_={
-                'open': stmt.excluded.open,
-                'high': stmt.excluded.high,
-                'low': stmt.excluded.low,
-                'close': stmt.excluded.close,
-                'volume': stmt.excluded.volume,
-                'adjusted_close': stmt.excluded.adjusted_close,
-                'data_source': stmt.excluded.data_source,
-                'updated_at': stmt.excluded.updated_at,
-            }
-        )
-        await db.execute(stmt)
+        # Yahoo-adjusted historical prices are not point-in-time stable: future
+        # dividends/splits can rewrite old OHLC values. Preserve existing
+        # historical rows and only update today's row, where intraday partials
+        # legitimately need EOD replacement.
+        if historical_rows:
+            stmt = pg_insert(PriceData).values(historical_rows)
+            stmt = stmt.on_conflict_do_nothing(constraint='uq_price_data')
+            await db.execute(stmt)
+
+        if live_rows:
+            stmt = pg_insert(PriceData).values(live_rows)
+            stmt = stmt.on_conflict_do_update(
+                constraint='uq_price_data',
+                set_={
+                    'open': stmt.excluded.open,
+                    'high': stmt.excluded.high,
+                    'low': stmt.excluded.low,
+                    'close': stmt.excluded.close,
+                    'volume': stmt.excluded.volume,
+                    'adjusted_close': stmt.excluded.adjusted_close,
+                    'data_source': stmt.excluded.data_source,
+                    'updated_at': stmt.excluded.updated_at,
+                }
+            )
+            await db.execute(stmt)
 
     async def _get_price_data_from_db(
         self,
@@ -942,13 +953,16 @@ class PriceDataService:
                 return None
 
         now = datetime.now(timezone.utc)
-        rows = []
+        today = now.date()
+        historical_rows = []
+        live_rows = []
         for date_idx, row in ticker_data.iterrows():
             price_date = date_idx.to_pydatetime()
             if price_date.tzinfo is None:
                 price_date = price_date.replace(tzinfo=timezone.utc)
 
-            rows.append({
+            target_rows = live_rows if price_date.date() >= today else historical_rows
+            target_rows.append({
                 'id': _uuid.uuid4(),
                 'ticker': ticker,
                 'date': price_date,
@@ -963,25 +977,36 @@ class PriceDataService:
                 'updated_at': now,
             })
 
-        if not rows:
+        if not historical_rows and not live_rows:
             return
 
-        stmt = pg_insert(PriceData).values(rows)
-        stmt = stmt.on_conflict_do_update(
-            constraint='uq_price_data',
-            set_={
-                'open': stmt.excluded.open,
-                'high': stmt.excluded.high,
-                'low': stmt.excluded.low,
-                'close': stmt.excluded.close,
-                'volume': stmt.excluded.volume,
-                'adjusted_close': stmt.excluded.adjusted_close,
-                'data_source': stmt.excluded.data_source,
-                'updated_at': stmt.excluded.updated_at,
-            }
+        if historical_rows:
+            stmt = pg_insert(PriceData).values(historical_rows)
+            stmt = stmt.on_conflict_do_nothing(constraint='uq_price_data')
+            await db.execute(stmt)
+
+        if live_rows:
+            stmt = pg_insert(PriceData).values(live_rows)
+            stmt = stmt.on_conflict_do_update(
+                constraint='uq_price_data',
+                set_={
+                    'open': stmt.excluded.open,
+                    'high': stmt.excluded.high,
+                    'low': stmt.excluded.low,
+                    'close': stmt.excluded.close,
+                    'volume': stmt.excluded.volume,
+                    'adjusted_close': stmt.excluded.adjusted_close,
+                    'data_source': stmt.excluded.data_source,
+                    'updated_at': stmt.excluded.updated_at,
+                }
+            )
+            await db.execute(stmt)
+        logger.info(
+            "Stored price records for %s: historical_insert_only=%d live_upsert=%d",
+            ticker,
+            len(historical_rows),
+            len(live_rows),
         )
-        await db.execute(stmt)
-        logger.info(f"Batch upserted {len(rows)} price records for {ticker}")
     
     async def _get_existing_dates_for_ticker(
         self,

yfinance_plus

@@ -1 +1 @@
-Subproject commit 674b7e45c8c79f3617dee9cffdd3f1438e4852cf
+Subproject commit e7011cabd7cd7853c3bc0fbd41601e004cc99ff4