web开发遇到的问题与解决思路

柔情只为你懂 2022-07-24 12:21 231阅读 0赞

# 最近开发一个船舶项目，遇到的问题 #

\[问题\]\[6\]：一个船舶上物料有很多分类,分类下面还存在分类,分类下面还存在分类，有一些分类下面只存在2级关系分类，有的是3级，有的是4级,如果是最终的类别还要带具体物料的名字以及基本信息：

--------------------

\[解决思路\]\[6\]：

1.创建表结构

**以下为关键字段**

<table> 
 <thead> 
  <tr> 
   <th align="left">字段名字</th> 
   <th align="left">类型</th> 
   <th align="left">备注</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td align="left">storesId</td> 
   <td align="left">bigint(20)</td> 
   <td align="left">物料ID，主键</td> 
  </tr> 
  <tr> 
   <td align="left">parentId</td> 
   <td align="left">bigint(20)</td> 
   <td align="left">父类id</td> 
  </tr> 
  <tr> 
   <td align="left">name</td> 
   <td align="left">varchar(64)</td> 
   <td align="left">物料名称</td> 
  </tr> 
  <tr> 
   <td align="left">storesType</td> 
   <td align="left">varchar(64)</td> 
   <td align="left">物料or类别</td> 
  </tr> 
 </tbody> 
</table>

--------------------

2.由于主键唯一性,所以parentId放上一类别的主键id，依次循环放置parentId，然后循环查询出来就行里,**这样依赖，看似解决了**，问题出在查询这里，因为存在2级3级4级等不同的依赖关系，查询要查询多少次呢？查询2次不行，4次也不行。

3.然后只能用递归查询来解决问题了，\[代码如下\]\[6\]

![这里写图片描述][20160523171204723]

4.查询以json格式传回前端页面

{
      "code": "200",
      "message": "OK",
      "data": [ { "displayOrder": 4, "status": "NORMAL", "createBy": 1, "createTime": 1463977621000, "updateBy": 0, "updateTime": null, "version": 0, "lastUpdate": 1463977786000, "storesId": 10067, "storesType": "CATEGORY", "code": "WL0002", "name": "物料2号", "specification": "12×1", "description": "没有描述", "unit": "T", "parentId": 0, "children": [ { "displayOrder": 4, "status": "NORMAL", "createBy": 1, "createTime": 1463987635000, "updateBy": 0, "updateTime": null, "version": 0, "lastUpdate": 1463987727000, "storesId": 10070, "storesType": "CATEGORY", "code": "SS0001", "name": "物料2号", "specification": "12×1", "description": "没有描述", "unit": "T", "parentId": 10067, "children": [ { "displayOrder": 4, "status": "NORMAL", "createBy": 1, "createTime": 1463991922000, "updateBy": 0, "updateTime": null, "version": 0, "lastUpdate": 1463991922000, "storesId": 10078, "storesType": "CATEGORY", "code": "SS0011", "name": "物料2号", "specification": "12×1", "description": "没有描述", "unit": "T", "parentId": 10070, "children": [ { "displayOrder": 4, "status": "NORMAL", "createBy": 1, "createTime": 1463991946000, "updateBy": 0, "updateTime": null, "version": 0, "lastUpdate": 1463991946000, "storesId": 10079, "storesType": "CATEGORY", "code": "SS0012", "name": "物料2号", "specification": "12×1", "description": "没有描述", "unit": "T", "parentId": 10078, "children": null } ] } ] }, { "displayOrder": 4, "status": "NORMAL", "createBy": 1, "createTime": 1463987643000, "updateBy": 0, "updateTime": null, "version": 0, "lastUpdate": 1463987732000, "storesId": 10071, "storesType": "CATEGORY", "code": "SS0002", "name": "物料2号", "specification": "12×1", "description": "没有描述", "unit": "T", "parentId": 10067, "children": null } ] }, { "displayOrder": 4, "status": "NORMAL", "createBy": 1, "createTime": 1463977646000, "updateBy": 0, "updateTime": null, "version": 0, "lastUpdate": 1463977787000, "storesId": 10068, "storesType": "CATEGORY", "code": "WL0003", "name": "物料2号", "specification": "12×1", "description": "没有描述", "unit": "T", "parentId": 0, "children": [ { "displayOrder": 4, "status": "NORMAL", "createBy": 1, "createTime": 1463991817000, "updateBy": 0, "updateTime": null, "version": 0, "lastUpdate": 1463991816000, "storesId": 10076, "storesType": "CATEGORY", "code": "SS0009", "name": "物料2号", "specification": "12×1", "description": "没有描述", "unit": "T", "parentId": 10068, "children": null }, { "displayOrder": 4, "status": "NORMAL", "createBy": 1, "createTime": 1463991865000, "updateBy": 0, "updateTime": null, "version": 0, "lastUpdate": 1463991864000, "storesId": 10077, "storesType": "CATEGORY", "code": "SS0010", "name": "物料2号", "specification": "12×1", "description": "没有描述", "unit": "T", "parentId": 10068, "children": null } ] }, { "displayOrder": 4, "status": "NORMAL", "createBy": 1, "createTime": 1463977660000, "updateBy": 0, "updateTime": null, "version": 0, "lastUpdate": 1463977790000, "storesId": 10069, "storesType": "CATEGORY", "code": "WL0004", "name": "物料2号", "specification": "12×1", "description": "没有描述", "unit": "T", "parentId": 0, "children": null }, { "displayOrder": 4, "status": "NORMAL", "createBy": 1, "createTime": 1463991048000, "updateBy": 0, "updateTime": null, "version": 0, "lastUpdate": 1463991047000, "storesId": 10072, "storesType": "CATEGORY", "code": "SS0003", "name": "物料2号", "specification": "12×1", "description": "没有描述", "unit": "T", "parentId": 0, "children": null }, { "displayOrder": 4, "status": "NORMAL", "createBy": 1, "createTime": 1463991240000, "updateBy": 0, "updateTime": null, "version": 0, "lastUpdate": 1463991240000, "storesId": 10073, "storesType": "CATEGORY", "code": "SS0004", "name": "物料2号", "specification": "12×1", "description": "没有描述", "unit": "T", "parentId": 0, "children": null }, { "displayOrder": 4, "status": "NORMAL", "createBy": 1, "createTime": 1463991611000, "updateBy": 0, "updateTime": null, "version": 0, "lastUpdate": 1463991611000, "storesId": 10074, "storesType": "CATEGORY", "code": "SS0005", "name": "物料2号", "specification": "12×1", "description": "没有描述", "unit": "T", "parentId": 0, "children": null }, { "displayOrder": 4, "status": "NORMAL", "createBy": 1, "createTime": 1463991811000, "updateBy": 0, "updateTime": null, "version": 0, "lastUpdate": 1463991815000, "storesId": 10075, "storesType": "CATEGORY", "code": "SS0008", "name": "物料2号", "specification": "12×1", "description": "没有描述", "unit": "T", "parentId": 0, "children": null } ] }

5.如果有更好的解决思路,可以留言交流。

[20160523171204723]: /images/20220722/7d44b35a45f343d4982027d376f7da47.png