sourcecode/server/data/src/main/java/com/qxgmat/data/relation/mapping/UserTextbookEnrollRelationMapper.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.qxgmat.data.relation.UserTextbookEnrollRelationMapper">
  <resultMap id="IdMap" type="com.qxgmat.data.dao.entity.UserTextbookEnroll">
    <!--
      WARNING - @mbg.generated
    -->
    <id column="id" jdbcType="INTEGER" property="id" />
  </resultMap>
  <resultMap id="NumberMap" type="com.qxgmat.data.relation.entity.TextbookEnrollNumberRelation">
    <!--
      WARNING - @mbg.generated
    -->
    <id column="month" jdbcType="TIMESTAMP" property="month" />
    <id column="number" jdbcType="INTEGER" property="number" />
  </resultMap>
  <sql id="Id_Column_List">
    <!--
      WARNING - @mbg.generated
    -->
    ute.`id`
  </sql>

  <!--
    统计报名人数
  -->
  <select id="groupByMonth" resultMap="NumberMap">
    select
    count(ute.`id`) as `number`, ute.`month` as `month`
    from `user_textbook_enrool` ute
    where 1
    <if test="startTime != null">
      and ute.`month` &gt; #{startTime,jdbcType=VARCHAR}
    </if>
    <if test="endTime != null">
      and ute.`month` &lt; #{endTime,jdbcType=VARCHAR}
    </if>
  </select>

</mapper>