sql select join progress

backends/tests/QueryTest.cpp

@@ -179,4 +179,51 @@ TEST_CASE_METHOD(QueryFixture, " Select statement with foreign key", "[session]"
 
   db.drop().table("flight").execute();
   db.drop().table("airplane").execute();
+}
+
+TEST_CASE_METHOD(QueryFixture, " Select statement with foreign key and join", "[session][join]") {
+  db.create()
+    .table<airplane>("airplane")
+    .execute();
+
+  db.create()
+    .table<flight>("flight")
+    .execute();
+
+  std::vector<entity<airplane>> planes {
+    make_entity<airplane>(1, "Airbus", "A380"),
+    make_entity<airplane>(2, "Boeing", "707"),
+    make_entity<airplane>(3, "Boeing", "747")
+  };
+
+  for (const auto &plane : planes) {
+    auto res = db.insert().into<airplane>("airplane").values(*plane).execute();
+    REQUIRE(res == 1);
+  }
+
+  auto count = db.select({count_all()}).from("airplane").fetch_value<int>();
+  REQUIRE(count == 3);
+
+  std::vector<entity<flight>> flights {
+    make_entity<flight>(4, planes.at(0), "hans"),
+    make_entity<flight>(5, planes.at(0), "otto"),
+    make_entity<flight>(6, planes.at(1), "george"),
+    make_entity<flight>(7, planes.at(2), "paul")
+  };
+
+  for (const auto &f : flights) {
+    auto res = db.insert().into<flight>("flight").values(*f).execute();
+    REQUIRE(res == 1);
+  }
+
+  auto f = *db.select<flight>().from("flight").fetch_all<flight>().begin();
+  REQUIRE(f.id == 4);
+  REQUIRE(f.pilot_name == "hans");
+  REQUIRE(f.airplane.get() != nullptr);
+  REQUIRE(f.airplane->id == 1);
+
+  db.select({"f.id", "ap.brand", "f.pilot_name"}).from("flight", "f").join("airplane", join_type_t::INNER, "ap").on("f.airplane_id", "ap.id");
+  db.drop().table("flight").execute();
+  db.drop().table("airplane").execute();
+
 }