implement SelectOne and multiple

add Fixtures

src/test/resources/fixtures/init.sql

@@ -0,0 +1,20 @@
+create table if not exists test
+(
+    id serial not null
+        constraint test_pk
+            primary key,
+    name text
+);
+
+create table if not exists test2
+(
+    id serial not null,
+    title text,
+    test_id integer
+        constraint test2_test_id_fk
+            references test
+);
+INSERT INTO public.test (id, name) VALUES (1, 'plop');
+INSERT INTO public.test2 (id, title, test_id) VALUES (1, 'plop', 1);
+INSERT INTO public.test2 (id, title, test_id) VALUES (2, 'plip', 1);
+INSERT INTO public.test2 (id, title, test_id) VALUES (3, 'ttt', null);