diff --git a/make_post_sell/views/misc.py b/make_post_sell/views/misc.py
index 0fc778e..721ec97 100644
--- a/make_post_sell/views/misc.py
+++ b/make_post_sell/views/misc.py
@@ -51,13 +51,12 @@ def ask_for_on_demand_tls(request):
     """
     domain_name_requesting_tls = request.params.get("domain")
     if domain_name_requesting_tls:
-        # "SELECT domain_name FROM mps_shop;"
-        result = request.dbsession.execute(text("SELECT domain_name FROM mps_shop;"))
-        rows = result.all()
-        registered_domains = [r[0] for r in rows]
-        if domain_name_requesting_tls in registered_domains:
-            return Response(status_code=200)
-    return Response(status_code=401)
+        query = text("SELECT EXISTS (SELECT 1 FROM mps_shop WHERE domain_name = :domain_name)")
+        result = request.dbsession.execute(query, {'domain_name': domain_name_requesting_tls})
+        exists = result.scalar()
+        if exists:
+            return Response(status=200)
+    return Response(status=401)
 
 
 # I set require_csfr to false because new browsers