线上课-学员返回学员的第一次学习时间

src/main/resources/mapper/UserCourseHourRecordMapper.xml

@@ -128,4 +128,22 @@
         </if>
         GROUP BY `user_id`;
     </select>
+    <select id="getUserCourseHourUserFirstCreatedAt"
+            resultType="xyz.playedu.api.types.mapper.UserCourseHourRecordUserFirstCreatedAtMapper">
+        SELECT `t1`.`created_at`, `t1`.`user_id`
+        FROM `user_course_hour_records` AS `t1`
+        INNER JOIN (SELECT `t2`.`user_id`, min(`t2`.`created_at`) as `created_at`
+        FROM `user_course_hour_records` AS `t2`
+        WHERE `t2`.`course_id` = #{courseId}
+        <if test="userIds != null and #{userIds}.size() > 0">
+            AND `t2`.`user_id` IN (<foreach collection="userIds" item="userId" separator=",">#{userId}</foreach>)
+        </if>
+        GROUP BY `t2`.`user_id`) AS `t3`
+        ON `t3`.`user_id` = `t1`.`user_id`
+        AND `t3`.`created_at` = `t1`.`created_at`
+        WHERE `t1`.`course_id` = #{courseId}
+        <if test="userIds != null and #{userIds}.size() > 0">
+            AND `t1`.`user_id` IN (<foreach collection="userIds" item="userId" separator=",">#{userId}</foreach>)
+        </if>
+    </select>
 </mapper>