diff --git a/db/db-core/src/lib.rs b/db/db-core/src/lib.rs
index fdb4e390..163f6445 100644
--- a/db/db-core/src/lib.rs
+++ b/db/db-core/src/lib.rs
@@ -122,6 +122,9 @@ pub trait MCDatabase: std::marker::Send + std::marker::Sync + CloneSPDatabase {
 
     /// get a user's password
     async fn get_password(&self, l: &Login) -> DBResult<NameHash>;
+
+    /// update user's password
+    async fn update_password(&self, p: &NameHash) -> DBResult<()>;
 }
 
 /// Trait to clone MCDatabase
diff --git a/db/db-core/src/tests.rs b/db/db-core/src/tests.rs
index d46c2a46..e2ef2098 100644
--- a/db/db-core/src/tests.rs
+++ b/db/db-core/src/tests.rs
@@ -38,7 +38,7 @@ pub async fn database_works<'a, T: MCDatabase>(db: &T, p: &Register<'a>) {
     assert_eq!(name_hash.username, p.username, "username matches");
 
     // with email
-    let name_hash = db
+    let mut name_hash = db
         .get_password(&Login::Email(p.email.as_ref().unwrap()))
         .await
         .unwrap();
@@ -54,6 +54,19 @@ pub async fn database_works<'a, T: MCDatabase>(db: &T, p: &Register<'a>) {
         db.username_exists(p.username).await.unwrap(),
         "user is registered so username should exsit"
     );
+
+    // update password test. setting password = username
+    name_hash.hash = name_hash.username.clone();
+    db.update_password(&name_hash).await.unwrap();
+
+    let name_hash = db.get_password(&Login::Username(p.username)).await.unwrap();
+    assert_eq!(
+        name_hash.hash, p.username,
+        "user password matches with changed value"
+    );
+    assert_eq!(name_hash.username, p.username, "username matches");
+
+    // deleting user for re-registration with email = None
     db.delete_user(p.username).await.unwrap();
     assert!(
         !db.username_exists(p.username).await.unwrap(),