导出系统数据初步完成（可以输出到控制台）

bookshelfplus/src/main/resources/mapping/BookDOMapper.xml

@@ -294,4 +294,11 @@
     left join book_info on user_book_favorites_relation.book_id = book_info.id
     where user_book_favorites_relation.user_id = #{userId,jdbcType=INTEGER}
   </select>
+  <select id="selectAll" resultMap="ResultMapWithBLOBs">
+    select
+    <include refid="Base_Column_List" />
+    ,
+    <include refid="Blob_Column_List" />
+    from book_info
+  </select>
 </mapper>