diff --git a/src/trading/trading_plan.py b/src/trading/trading_plan.py
index f9e55a2..0bb15b4 100644
--- a/src/trading/trading_plan.py
+++ b/src/trading/trading_plan.py
@@ -82,8 +82,8 @@ def create_trading_plan_table():
             id UInt32,
             plan_name String,
             status String,
-            created_at DateTime,
-            updated_at DateTime,
+            created_at DateTime64(3),
+            updated_at DateTime64(3),
             
             timeframe String,
             market_focus String,
@@ -123,9 +123,8 @@ def create_trading_plan_table():
             fundamental_criteria Nullable(String),
             options_strategy_details Nullable(String)
         )
-        ENGINE = MergeTree()
-        PRIMARY KEY (id)
-        ORDER BY (id, created_at)
+        ENGINE = ReplacingMergeTree(updated_at)
+        ORDER BY (id)
         """
         client.execute(query)