sqlgen/tests/mysql/test_union_in_join.cpp

#ifndef SQLGEN_BUILD_DRY_TESTS_ONLY

#include <gtest/gtest.h>

#include <rfl.hpp>
#include <rfl/json.hpp>
#include <sqlgen.hpp>
#include <sqlgen/mysql.hpp>
#include <vector>

#include "sqlgen/mysql/to_sql.hpp"

namespace test_union_in_join {

struct User1 {
  std::string name;
  int age;
};

struct User2 {
  std::string name;
  int age;
};

struct User3 {
  int age;
  std::string name;
};

struct Login {
  int id;
  std::string username;
};

TEST(mysql, test_union_in_join) {
  using namespace sqlgen;
  using namespace sqlgen::literals;

  const auto credentials = sqlgen::mysql::Credentials{.host = "localhost",
                                                      .user = "sqlgen",
                                                      .password = "password",
                                                      .dbname = "mysql"};

  const auto conn = sqlgen::mysql::connect(credentials)
                        .and_then(sqlgen::drop<User1> | sqlgen::if_exists)
                        .and_then(sqlgen::drop<User2> | sqlgen::if_exists)
                        .and_then(sqlgen::drop<User3> | sqlgen::if_exists)
                        .and_then(sqlgen::drop<Login> | sqlgen::if_exists);

  const auto user1 = User1{.name = "John", .age = 30};
  sqlgen::write(conn, user1);

  const auto user2 = User2{.name = "Jane", .age = 25};
  sqlgen::write(conn, user2);

  const auto user3 = User3{.age = 40, .name = "Joe"};
  sqlgen::write(conn, user3);

  const auto login = Login{.id = 1, .username = "John"};
  sqlgen::write(conn, login);

  const auto s1 = sqlgen::select_from<User1>("name"_c, "age"_c);
  const auto s2 = sqlgen::select_from<User2>("name"_c, "age"_c);
  const auto s3 = sqlgen::select_from<User3>("name"_c, "age"_c);

  const auto united = sqlgen::unite<std::vector<User1>>(s1, s2, s3);

  const auto sel = select_from<Login, "t1">("id"_t1, "username"_t1) |
                   inner_join<"t2">(united, "username"_t1 == "name"_t2) |
                   where("id"_t1 == 1) | to<std::vector<Login>>;

  const auto query = sqlgen::mysql::to_sql(sel);

  const auto result = sel(conn);

  const auto users = result.value();

  EXPECT_EQ(
      query,
      R"(SELECT t1.`id`, t1.`username` FROM `Login` t1 INNER JOIN (SELECT t.`name`, t.`age` FROM (SELECT `name`, `age` FROM `User1`) t UNION SELECT t.`name`, t.`age` FROM (SELECT `name`, `age` FROM `User2`) t UNION SELECT t.`name`, t.`age` FROM (SELECT `name`, `age` FROM `User3`) t) t2 ON t1.`username` = t2.`name` WHERE t1.`id` = 1)");

  EXPECT_EQ(users.size(), 1);
  EXPECT_EQ(users.at(0).id, 1);
  EXPECT_EQ(users.at(0).username, "John");
}

}  // namespace test_union_in_join

#endif  // SQLGEN_BUILD_DRY_TESTS_ONLY