diff --git a/initdb/schema.sql b/initdb/schema.sql
index c75e3de5094d916c74f057492c3ba162c704cfc4..b91c7e760f42c5903e32d052853eff6dcd0a2887 100644
--- a/initdb/schema.sql
+++ b/initdb/schema.sql
@@ -25,6 +25,7 @@ CREATE TABLE comments (
     user_id int NOT NULL,
     video_id int NOT NULL,
     content text NOT NULL,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
     FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE,
     FOREIGN KEY (video_id) REFERENCES videos(id) ON DELETE CASCADE
 );
@@ -34,6 +35,7 @@ CREATE TABLE reply (
     creator_id int NOT NULL,
     content text NOT NULL,
     comment_id int NOT NULL,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
     FOREIGN KEY (comment_id) REFERENCES comments(id) ON DELETE CASCADE,
     FOREIGN KEY (creator_id) REFERENCES users(id) ON DELETE CASCADE
 );