diff --git a/src/api/query.rs b/src/api/query.rs
index bd5b42f..3eec130 100644
--- a/src/api/query.rs
+++ b/src/api/query.rs
@@ -385,10 +385,14 @@ pub trait ExtendedQueryHandler: Send + Sync {
     /// `READY_FOR_QUERY` response to client
     async fn on_sync<C>(&self, client: &mut C, _message: PgSync) -> PgWireResult<()>
     where
-        C: ClientInfo + Sink<PgWireBackendMessage> + Unpin + Send + Sync,
+        C: ClientInfo + ClientPortalStore + Sink<PgWireBackendMessage> + Unpin + Send + Sync,
+        C::PortalStore: PortalStore<Statement = Self::Statement>,
         C::Error: Debug,
         PgWireError: From<<C as Sink<PgWireBackendMessage>>::Error>,
     {
+        // cleanup all portals
+        client.portal_store().clear_portals();
+
         client
             .send(PgWireBackendMessage::ReadyForQuery(ReadyForQuery::new(
                 client.transaction_status(),
diff --git a/src/api/store.rs b/src/api/store.rs
index fd7dd4f..4a28642 100644
--- a/src/api/store.rs
+++ b/src/api/store.rs
@@ -17,6 +17,8 @@ pub trait PortalStore: Send + Sync {
 
     fn rm_portal(&self, name: &str);
 
+    fn clear_portals(&self);
+
     fn get_portal(&self, name: &str) -> Option<Arc<Portal<Self::Statement>>>;
 }
 
@@ -56,6 +58,11 @@ impl<S: Clone + Send + Sync> PortalStore for MemPortalStore<S> {
         guard.remove(name);
     }
 
+    fn clear_portals(&self) {
+        let mut guard = self.portals.write().unwrap();
+        guard.clear();
+    }
+
     fn get_portal(&self, name: &str) -> Option<Arc<Portal<Self::Statement>>> {
         let guard = self.portals.read().unwrap();
         guard.get(name).cloned()