【Lazy ORM 查询使用手册】1.2.2-JDK17-SNAPSHOT

Gitee

版本信息 1.2.2-JDK17-SNAPSHOT

新增 inOr查询 防止in查询索引失效

用法

       public void select() {
            LazyUserTest lazyUserTest = new LazyUserTest();
            lazyUserTest.setUsername("紧");
            lazyUserTest.setSex(LazyUserTest.Sex.MAN);
            lazyUserTest.setId(12L);
            lazyLambdaStream.upsert(lazyUserTest);
            lazyLambdaStream.update(lazyUserTest, LazyWrappers.<LazyUserTest>lambdaWrapper().eq(LazyUserTest::getSex, LazyUserTest.Sex.MAN));
        
            List<LazyUserTest> lazyUserTests = lazyLambdaStream.selectList(LazyWrappers.<LazyUserTest>lambdaWrapper()
                    .inOr(LazyUserTest::getAge, List.of(18, 19, 20))
            );
            System.out.println("18、19、20 age user:" + lazyUserTests);
            // 打印信息
            // 执行类型: =====> SELECT  
            //执行sql: =====>  SELECT  lazy_user_test.birthday as birthday , lazy_user_test.sex as sex , lazy_user_test.id as id , lazy_user_test.username as username , lazy_user_test.is_deleted as is_deleted , lazy_user_test.age as age  from lazy_user_test where  (   lazy_user_test.age =  18 or lazy_user_test.age =  19 or lazy_user_test.age =  20  )  and  is_deleted  = false
            // 18、19、20 age user:[]
        }

selectOne 查询

       public void select() {
            LazyUserTest lazyUserTest = new LazyUserTest();
            lazyUserTest.setUsername("紧");
            lazyUserTest.setSex(LazyUserTest.Sex.MAN);
            lazyUserTest.setId(12L);
            lazyLambdaStream.upsert(lazyUserTest);
            lazyLambdaStream.update(lazyUserTest, LazyWrappers.<LazyUserTest>lambdaWrapper().eq(LazyUserTest::getSex, LazyUserTest.Sex.MAN));
        
            LazyUserTest lazyUserTest = lazyLambdaStream.selectOne(LazyWrappers.<LazyUserTest>lambdaWrapper()
                    .eq(LazyUserTest::getId, 12L)
                    .eq(LazyUserTest::getIsDeleted, false)
            );
            System.out.println(" user :" + lazyUserTest);
            // 打印信息
            // 执行类型: =====> SELECT  
            //执行sql: =====>  SELECT  lazy_user_test.birthday as birthday , lazy_user_test.sex as sex , lazy_user_test.id as id , lazy_user_test.username as username , lazy_user_test.is_deleted as is_deleted , lazy_user_test.age as age  from lazy_user_test where   lazy_user_test.id =  12    and  is_deleted  = false
            // 18、19、20 age user:[]
        }

统计数据

    @Test
    public void  count(){
        Long count = lazyLambdaStream.count(LazyWrappers.<LazyUserTest>lambdaWrapper()
                .eq(LazyUserTest::getIsDeleted, false)
                .eq(LazyUserTest::getSex, LazyUserTest.Sex.MAN)
                .gt(LazyUserTest::getAge, 10)
                .gt(LazyUserTest::getBirthday, LocalDateTime.now()));
        // 如同执行如下sql select count(1) from lazy_user_test where  lazy_user_test.is_deleted  = false  and  lazy_user_test.sex  = 'MAN'  and  lazy_user_test.age  > 10  and  lazy_user_test.birthday  > '2024-02-06 20:21:03'  and  lazy_user_test.is_deleted  = false
        System.out.println("lazyLambdaStream.count:"+count);
    }

验证数据是否存在

    @Test
    public void  exists(){
        boolean exists = lazyLambdaStream.exists(LazyWrappers.<LazyUserTest>lambdaWrapper()
                .eq(LazyUserTest::getIsDeleted, false)
                .eq(LazyUserTest::getSex, LazyUserTest.Sex.MAN)
                .gt(LazyUserTest::getAge, 10)
                .gt(LazyUserTest::getBirthday, LocalDateTime.now()));
        // 如同执行如下sql select count(1) from lazy_user_test where  lazy_user_test.is_deleted  = false  and  lazy_user_test.sex  = 'MAN'  and  lazy_user_test.age  > 10  and  lazy_user_test.birthday  > '2024-02-06 20:21:03'  and  lazy_user_test.is_deleted  = false
        System.out.println("lazyLambdaStream.exists:"+exists);
    }

查询某一个字段

    @Test
    public void  selectName(){
        String userName = lazyLambdaStream.selectOne(LazyWrappers.<LazyUserTest>lambdaWrapper()
                .eq(LazyUserTest::getId, 1)
                .eq(LazyUserTest::getIsDeleted, false)
                        .onlyUseAs()
                        .as(LazyUserTest::getUsername,LazyUserTest::getUsername),
                String.class);
        // SELECT  lazy_user_test.username as username  from lazy_user_test where  lazy_user_test.id  = 1  and  lazy_user_test.is_deleted  = false  and  lazy_user_test.is_deleted  = false
        System.out.println("只查询用户ID为1 的用户名称:"+userName);
    }
    

查询部分字段减少IO

    @Test
    public void  selectNameIdAge(){
        LazyUserTest userNameIdAge = lazyLambdaStream.selectOne(LazyWrappers.<LazyUserTest>lambdaWrapper()
                        .eq(LazyUserTest::getId, 1)
                        .eq(LazyUserTest::getIsDeleted, false)
                        .onlyUseAs()

                        .as(LazyUserTest::getId,LazyUserTest::getId)
                        .as(LazyUserTest::getAge,LazyUserTest::getAge)
                        .as(LazyUserTest::getUsername,LazyUserTest::getUsername)
                ,
                LazyUserTest.class);
        // SELECT  lazy_user_test.id as id , lazy_user_test.username as username , lazy_user_test.age as age  from lazy_user_test where  lazy_user_test.id  = 1  and  lazy_user_test.is_deleted  = false  and  lazy_user_test.is_deleted  = false
        System.out.println("只查询用户ID为1 的用户名称、ID、age:"+userNameIdAge);
    }

关联查询

List<Menu> menuList = lazyLambdaStream.selectList(LazyWrappers.<RoleMenuDO>lambdaWrapper()
                        .eq(RoleMenuDO::getIsDeleted, false)
                        .eq(RoleMenuDO::getRoleId, role.getId())
                        .internalJoin(LazyWrappers.<RoleMenuDO, MenuDO>lambdaWrapperJoin()
                                .eqo(RoleMenuDO::getIsDeleted, false)
                                .eqo(RoleMenuDO::getRoleId, role.getId())
                                .eq(RoleMenuDO::getMenuId, MenuDO::getId)
                                .eqRighto(MenuDO::getIsDeleted, false)
                        )
                        .onlyUseAs()
                        .as(Menu.class),
                        Menu.class
                );