Add experimental code (commented out) for DELETE JOIN support

This would be needed to support object relationships in the erase_query()
functionality.

2 files changed, 52 insertions, 2 deletions

diff --git a/common/erase-query/driver.cxx b/common/erase-query/driver.cxx
index 67d4e8d..2137377 100644
--- a/common/erase-query/driver.cxx
+++ b/common/erase-query/driver.cxx
@@ -63,7 +63,8 @@ main (int argc, char* argv[])
 
     {
       transaction t (db->begin ());
-      assert (db->erase_query<object> ("id < 3") == 2);
+      assert (db->erase_query<object> (
+                "common_erase_query_object.id < 3") == 2);
       db->erase_query<object> ();
       t.commit ();
     }
@@ -79,6 +80,38 @@ main (int argc, char* argv[])
       t.commit ();
     }
 
+    // Test predicates involving object pointers (DELETE JOIN).
+    //
+    /*
+    {
+      object o11 (1);
+      object o12 (2);
+      object o13 (3);
+      object2 o2;
+
+      o11.o2 = &o2;
+      o2.num = 123;
+
+      o12.o1 = &o13;
+      o13.num = 123;
+
+      transaction t (db->begin ());
+      db->persist (o2);
+      db->persist (o13);
+      db->persist (o12);
+      db->persist (o11);
+      t.commit ();
+    }
+
+    {
+      transaction t (db->begin ());
+      assert (db->erase_query<object> (query::o1::num == 123) == 1);
+      assert (db->erase_query<object> (query::o2::num == 123) == 1);
+      db->erase_query<object> ();
+      t.commit ();
+    }
+    */
+
     // Make sure container data is deleted.
     //
     {
diff --git a/common/erase-query/test.hxx b/common/erase-query/test.hxx
index be5539f..781eedd 100644
--- a/common/erase-query/test.hxx
+++ b/common/erase-query/test.hxx
@@ -10,15 +10,18 @@
 
 #include <odb/core.hxx>
 
+struct object2;
+
 #pragma db object
 struct object
 {
   object (unsigned long id)
-      : id_ (id)
+      : id_ (id), o1 (0), o2 (0)
   {
   }
 
   object ()
+      : o1 (0), o2 (0)
   {
   }
 
@@ -26,6 +29,20 @@ struct object
   unsigned long id_;
 
   std::vector<int> v;
+
+  int num;
+
+  object* o1;
+  object2* o2;
+};
+
+#pragma db object
+struct object2
+{
+  #pragma db id auto
+  unsigned long id_;
+
+  int num;
 };
 
 #endif // TEST_HXX