Mybatis 传参问题

问题一：
之前在mysql客户端上编写sql习惯导致使用mybatis 将字符串参数逗号拼接进行传值 in(1,2,3) 一直返回一条数据 ，控制台输出的sql也没问题反复找不出所以然，经过同事指导才解决…

//错误示例 原因：使用in 参数传值为1,2,3  mybaits底层不会解析  只能返回一条数据
	List<String> list = usersMapper.getUserAccountByUsersId("1,2,3");
		Assert.assertNotNull(list);

<select id="getUserAccountByUsersId"  resultType="java.lang.String">
  	 select uas.userAccountId as userAccountIds  from users u LEFT JOIN user_account uc ON u.id = uc.userId AND uc.`status` = 1
	 LEFT JOIN user_account_settlement uas on u.id = uas.userId AND uas.`status` = 1
	 WHERE u.deleted_at IS NULL AND u.id in #{usersids,jdbcType=VARCHAR}
  </select>

//正确示例  将参数值存入list中 1  2   3
@Test
	public void select () {
		List<String> ids = new ArrayList<String>();
		ids.add("1");
		ids.add("2");
		ids.add("3");
		List<String> list = usersMapper.getUserAccountByUsersId(ids);
		Assert.assertNotNull(list);
	}

//foreach 进行集合遍历
<select id="getUserAccountByUsersId"  resultType="java.lang.String">
  	 select uas.userAccountId as userAccountIds  from users u LEFT JOIN user_account uc ON u.id = uc.userId AND uc.`status` = 1
	 LEFT JOIN user_account_settlement uas on u.id = uas.userId AND uas.`status` = 1
	 WHERE u.deleted_at IS NULL AND u.id in 
	 	<foreach collection="list" item="uid" index="index" open="(" close=")" separator=",">  
            #{uid}  
        </foreach>
  </select>

问题二：
mybatis 使用Map<String，Object>进行参数传递（map中有String,List类型）

//正确示例
	@Test
	public void selectEntryExitCount() {
		List<String> arr = new ArrayList<String>();
		arr.add("1");
		arr.add("2");
		arr.add("3");
		
		HashMap<String, Object> params = new HashMap<>();
		params.put("user_account_ids", arr);
		params.put("start_date", "2019-1-1");
		params.put("end_date", "2019-1-1");
		Assert.assertNotNull(entryExitCountMapper.selectEntryExitCount(params));
	}

<select id="selectMerchantsCountOrder" parameterType="java.util.HashMap" resultType="java.util.HashMap">
  		SELECT SUM(loadings.money+overs.money+fails.money) as acount_money FROM 
		(
		SELECT IFNULL(SUM(money),0) as money FROM entry_exit_account
		where 1=1 and status = 0
			<if test="user_account_ids.size() > 0">
				 and userAccountId in 
				<foreach collection="user_account_ids" open="(" close=")" separator="," item="id">
			        #{id}
			    </foreach> 
			</if>
        <if test="start_date != null and start_date != ''"> AND date <![CDATA[>=]]> #{start_date}</if>
        <if test="end_date != null and end_date != ''"> AND date <![CDATA[<=]]>#{end_date}</if>
		) loadings,

注意：<if test="_parameter.containsKey('user_account_ids')"> 判空不推荐使用因为参数无值会传递null值， 注意括号中的单引号不能少！！！
map中集合遍历 foreach  collection map中的key(集合)  注意不要使用#{params.userAccountId}报错  也不要params.userAccountId 都不行