1、使用了xml形式的mapper。 2、不想在select查询中大量使用<if>标签来判断条件是否存在而加入条件。 二、步骤 1、自定义wrapper继承QueryWrapper: importcom.baomidou.mybatisplus.core.conditions.query.QueryWrapper;importorg.apache.shiro.util.StringUtils;publicclassCustomWrapper<T>extendsQueryWrapper<T>{/*** if...
<select id="yktestOrder" resultType="com.yuxun.fantuan.security.entity.User"> select u.id, u.username FROM user u WHERE 1 = 1 <if test="null != ids and ids.size > 0"> AND u.id IN <foreach item="item" index="index" collection="ids" open="(" separator="," close=")"> #...
pid=#{pid} </if> </where> </select> 测试: 代码语言:javascript 复制 @Test @DisplayName("自定义返回结果有入参") public void testSelectProductWithCategoryByMap(){ Map<String,Object> params=new HashMap<>(4); params.put("categoryId",1l); params.put("pid",5); List<Map> productList=...
select id= "findAll" resultMap= "userMap"> SELECT *,o.id oid FROM USER u,orders o WHERE u.id=o.uid </ select> 总结来看,一对多相比于一对一就是在那个“一”中增添了封装“多”的属性而已,然后稍微调整一下SQL 3.多对多 多用户多角色 多对多的建表原则是引入一张中间表,用于维护外键,就是...
@ComponentpublicclassDecryptInterceptorimplementsInterceptor{@OverridepublicObjectintercept(Invocation invocation)throws Throwable{Object resultObject=invocation.proceed();try{if(Objects.isNull(resultObject)){returnnull;}//基于selectListif(resultObjectinstanceofArrayList){ArrayList resultList=(ArrayList)resultObject;...
@Select({"<script>", "select g.id,g.game_id,g.game_name, g.main_pic,g.detail_pic, g.download_sum,g.user_sum,g.recharge_sum,g.sort_num, " + " g.online_type,g.download_url,g.register_point, g.mission_point,g.type_id,g.create_id,g.create_time,g.update_id, g.update_time...
<select id="getStuByConditionIf" resultType="com.person.Students"> SELECT * FROM student WHERE <!-- test:判断表达式(OGNL) OGNL参照PPT或者官方文档。 c:if test 从参数中取值进行判断 --> <if test="id!=null"> id=#{id} </if> <if test="name!=null and name!="""> ...
mysql中sum与if,case when 结合使用 2019-11-28 19:15 −1.sum与if结合使用 如图:数据表中,count_money 字段可为正,可为负。为正表示收入,负表示支出。 统计总收入,总支出。 select sum(if(count_money > 0, count_money, 0)) as sum_receipt, s... ...
= null and dept.deptName != ''">ANDdept_namelikeconcat('%',#{dept.deptName},'%')</if><iftest="dept.status != null and dept.status != ''">ANDstatus=#{dept.status}</if><!--数据范围过滤-->${dept.params.dataScope}orderbyd.parent_id,d.order_num</select>...
(condition);Integer total = mapper.selectCount(wrapper);if (limit == null || limit <= 0 || total == 0) {return Collections.emptyList();}List<T> list = Optional.of(limit).filter(l -> l > total).map(l -> mapper.selectList(wrapper)).orElseGet(() -> mapper.selectList(wrapper....