added timestamp code, support columns for group by and order by and tested load has-many eager code

test/backends/QueryTest.cpp

@@ -12,6 +12,9 @@
 #include "models/flight.hpp"
 #include "models/person.hpp"
 #include "models/recipe.hpp"
+#include "models/shipment.hpp"
+
+#include "../test/utils/record_printer.hpp"
 
 using namespace matador::object;
 using namespace matador::query;
@@ -23,6 +26,8 @@ META_TABLE(ingredients, INGREDIENT, id, name);
 META_TABLE(recipe_ingredients, RECIPE_INGREDIENT, recipe_id, ingredient_id);
 META_TABLE(airplanes, AIRPLANE, id, brand, model);
 META_TABLE(flights, FLIGHT, id, airplane_id, pilot_name);
+META_TABLE(shipments, SHIPMENT, id, tracking_number)
+META_TABLE(packages, PACKAGE, id, weight, shipment)
 
 TEST_CASE_METHOD(QueryFixture, "Create table with foreign key relation", "[query][foreign][relation]") {
   auto result = repo.attach<airplane>("airplane")
@@ -605,4 +610,107 @@ TEST_CASE_METHOD(QueryFixture, "Select statement with many to many relationship"
     REQUIRE(row.at(3).as<std::string>().value() == std::get<3>(expected_result_two_joins[index]));
     ++index;
   }
+}
+
+void print(std::ostream& out, const record& row) {
+  for (const auto& f : row) {
+    out << f << " ";
+  }
+}
+
+TEST_CASE_METHOD(QueryFixture, "Test load entity with eager has many relation", "[query][has_many][eager]") {
+  auto result = repo.attach<package>("packages")
+    .and_then( [this] { return repo.attach<shipment>("shipments"); } );
+  // auto result = repo.attach<shipment>("shipments")
+  //   .and_then( [this] { return repo.attach<package>("packages"); } );
+  REQUIRE(result.is_ok());
+  tables_to_drop.emplace("shipments");
+  tables_to_drop.emplace("packages");
+
+  result = repo.create(db);
+  REQUIRE(result.is_ok());
+
+  const std::vector shipments {
+    object_ptr{new  shipment{1, "4711"}},
+    object_ptr{new  shipment{2, "0815"}}
+  };
+
+  using namespace matador::query::meta;
+
+  for (const auto &sh: shipments) {
+    auto res = query::insert()
+      .into(SHIPMENT, SHIPMENT)
+      .values(*sh)
+      .execute(db);
+    REQUIRE(res.is_ok());
+    REQUIRE(*res == 1);
+  }
+
+  auto count = query::select({count_all()})
+    .from(SHIPMENT)
+    .fetch_value<int>(db);
+  REQUIRE(count.is_ok());
+  REQUIRE(*count == 2);
+
+  std::vector packages {
+    object_ptr{new package{3, 15.4, shipments.at(0)}},
+    object_ptr{new package{4, 1.3, shipments.at(0)}},
+    object_ptr{new package{5, 30.9, shipments.at(1)}},
+    object_ptr{new package{6, 22.8, shipments.at(1)}},
+    object_ptr{new package{7, 17.2, shipments.at(1)}}
+  };
+
+  for (const auto &pkg: packages) {
+    auto res = query::insert()
+      .into(PACKAGE, PACKAGE)
+      .values(*pkg)
+      .execute(db);
+    REQUIRE(res.is_ok());
+    REQUIRE(*res == 1);
+  }
+
+  count = query::select({count_all()})
+    .from(PACKAGE)
+    .fetch_value<int>(db);
+  REQUIRE(count.is_ok());
+  REQUIRE(*count == 5);
+
+  auto pkgs = query::select({PACKAGE.id, PACKAGE.weight, PACKAGE.shipment, SHIPMENT.tracking_number})
+    .from(PACKAGE)
+    .join_left(SHIPMENT)
+    .on( PACKAGE.shipment == SHIPMENT.id )
+    .where( PACKAGE.weight > 20.0 && SHIPMENT.tracking_number == "0815" )
+    .group_by({PACKAGE.id, SHIPMENT.tracking_number})
+    .order_by(PACKAGE.weight).asc()
+    .limit( 5 )
+    .offset( 0 )
+    .fetch_all(db);
+
+  REQUIRE(pkgs.is_ok());
+
+  record_printer printer(std::cout);
+  printer.print(*pkgs);
+
+  auto shipment_records = query::select({SHIPMENT.tracking_number, SHIPMENT.id, PACKAGE.weight, PACKAGE.weight})
+    .from(SHIPMENT)
+    .join_left(PACKAGE)
+    .on( SHIPMENT.id == PACKAGE.shipment )
+    .fetch_all(db);
+
+  REQUIRE(shipment_records.is_ok());
+
+  printer.print(*shipment_records);
+
+  auto shipment_result = query::select({SHIPMENT.id, SHIPMENT.tracking_number, PACKAGE.id, PACKAGE.weight, PACKAGE.shipment})
+    .from(SHIPMENT)
+    .join_left(PACKAGE)
+    .on( SHIPMENT.id == PACKAGE.shipment )
+    .fetch_all<shipment>(db);
+
+  REQUIRE(shipment_result.is_ok());
+
+  std::cout << "\n";
+  for (const auto &s : *shipment_result) {
+    std::cout << s.id << " " << s.tracking_number << " packages: " << s.packages.size() << std::endl;
+  }
 }