mapper的xml文件中，语句中的参数如何编写

参数只有一个

<select id="countRegisterDay" resultType="java.lang.Integer">
      SELECT COUNT(*) FROM ucenter_member uc WHERE DATE(uc.gmt_create) = #{day}
</select>

Integer countRegisterDay(String day);

参数有多个

<select id="countRegisterDay" resultType="java.lang.Integer">
      SELECT COUNT(*) FROM ucenter_member uc WHERE DATE(uc.gmt_create) = #{0} or DATE(uc.gmt_create) = #{1}
</select>

Integer countRegisterDay(String day,String day2);

---

<select id="countRegisterDay" resultType="java.lang.Integer">
      SELECT COUNT(*) FROM ucenter_member uc WHERE DATE(uc.gmt_create) = #{day1} or DATE(uc.gmt_create) = #{day2}
</select>

Integer countRegisterDay(@Param("day1")String day,@Param("day2")String day2);