From d4865e4d10ae20a8e9e139c1818a945342aaff07 Mon Sep 17 00:00:00 2001
From: sascha <skuehl1972@gmail.com>
Date: Tue, 7 Jul 2026 08:23:43 +0200
Subject: [PATCH 1/2] collection proxy progress

---
 test/core/object/CollectionTest.cpp       |  9 +++++++++
 test/orm/query/DeleteQueryBuilderTest.cpp | 10 +++++++++-
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/test/core/object/CollectionTest.cpp b/test/core/object/CollectionTest.cpp
index 015e0ae..843e0ed 100644
--- a/test/core/object/CollectionTest.cpp
+++ b/test/core/object/CollectionTest.cpp
@@ -3,5 +3,14 @@
 #include "matador/object/collection.hpp"
 #include "matador/object/object.hpp"
 
+#include <iostream>
+
+using namespace matador::object;
+
 TEST_CASE("Test collection", "[collection]") {
+    collection<int> ints{{1,2,3,4}};
+
+    for (auto const& i : ints) {
+        std::cout << i << std::endl ;
+    }
 }
\ No newline at end of file
diff --git a/test/orm/query/DeleteQueryBuilderTest.cpp b/test/orm/query/DeleteQueryBuilderTest.cpp
index 6d71155..bd85157 100644
--- a/test/orm/query/DeleteQueryBuilderTest.cpp
+++ b/test/orm/query/DeleteQueryBuilderTest.cpp
@@ -72,7 +72,7 @@ TEST_CASE_METHOD(QueryFixture, "Test delete builder has many to many", "[query][
     .and_then( [&scm] { return scm.attach<ingredient>("ingredients"); } );
   REQUIRE(result.is_ok());
 
-  const std::vector ingredients {
+  std::vector ingredients {
     make_object<ingredient>(1, "Apple"),
     make_object<ingredient>(2, "Strawberry"),
     make_object<ingredient>(3, "Pineapple"),
@@ -82,12 +82,20 @@ TEST_CASE_METHOD(QueryFixture, "Test delete builder has many to many", "[query][
     make_object<ingredient>(7, "Beans")
   };
 
+  for (auto &i : ingredients) {
+    i.change_state(object_state::Persistent);
+  }
+
   std::vector recipes {
     make_object<recipe>(1, "Apple Pie", std::vector{ingredients[0], ingredients[3], ingredients[4]}),
     make_object<recipe>(2, "Strawberry Cake", std::vector{ingredients[5], ingredients[6]}),
     make_object<recipe>(3, "Pineapple Pie", std::vector{ingredients[0], ingredients[1], ingredients[2]})
   };
 
+  for (auto &r : recipes) {
+    r.change_state(object_state::Persistent);
+  }
+
   const auto contexts_by_type = to_contexts_by_name(scm, db->dialect());
   delete_query_builder<recipe> dqb(scm, contexts_by_type);
 

From 6ecda781f5273b01a43e8c37cf2b23449fe658f8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Sascha=20K=C3=BChl?= <skuehl1972@gmail.com>
Date: Mon, 20 Jul 2026 07:02:16 +0200
Subject: [PATCH 2/2] collection_proxy progress

---
 include/matador/object/collection_proxy.hpp | 31 +++++++++++++++------
 1 file changed, 22 insertions(+), 9 deletions(-)

diff --git a/include/matador/object/collection_proxy.hpp b/include/matador/object/collection_proxy.hpp
index 791aae3..35eb8e0 100644
--- a/include/matador/object/collection_proxy.hpp
+++ b/include/matador/object/collection_proxy.hpp
@@ -20,7 +20,11 @@ namespace matador::object {
 // relation<OwnerType, ForeignType>
 
 template < class RelationType >
-struct relation_iterator_traits;
+struct relation_iterator_traits {
+  static RelationType& value(RelationType& item) {
+    return item;
+  }
+};
 
 template < typename Type, typename OwnerType >
 struct relation_iterator_traits<relation<OwnerType, Type>> {
@@ -39,11 +43,17 @@ public:
   using iterator_category = std::forward_iterator_tag;
 
   collection_proxy_iterator() = default;
-  explicit collection_proxy_iterator(typename std::vector<RelationType>::iterator it)
+  collection_proxy_iterator(typename std::vector<RelationType>::iterator it)
   : it_(it) {}
 
-  reference operator*() { return *it_; }
-  pointer operator->() { return &*it_; }
+  reference operator*() {
+    return relation_iterator_traits<relation_type>::value(*it_);
+  }
+
+  pointer operator->() {
+    return &relation_iterator_traits<relation_type>::value(*it_);
+  }
+
   collection_proxy_iterator& operator++() {
     ++it_;
     return *this;
@@ -55,9 +65,10 @@ public:
     return !operator==(other);
   }
 
-  relation_type& relation() {
-    return *it_;
-  }
+  // relation_type& relation() {
+
+    // return *it_;
+  // }
 private:
   typename std::vector<RelationType>::iterator it_;
 };
@@ -67,8 +78,10 @@ class abstract_collection_proxy {
 public:
   using value_type = Type;
   using relation_type = RelationType;
-  using iterator = typename std::vector<value_type>::iterator;
-  using const_iterator = typename std::vector<value_type>::const_iterator;
+  // using iterator = typename std::vector<value_type>::iterator;
+  // using const_iterator = typename std::vector<value_type>::const_iterator;
+  using iterator = collection_proxy_iterator<value_type, relation_type>;
+  using const_iterator = collection_proxy_iterator<value_type, relation_type>;
 
   virtual ~abstract_collection_proxy() = default;