From afa28827b6aa5724141856852cda5177d3033075 Mon Sep 17 00:00:00 2001
From: weicw1996 <weicw1996@qq.com>
Date: Mon, 12 Oct 2026 14:49:30 +0800
Subject: [PATCH] =?UTF-8?q?fix(=E8=8D=AF=E5=88=86=E4=BA=AB):=20=E5=95=86?=
 =?UTF-8?q?=E5=93=81=E6=B8=85=E5=8D=95=E5=8E=BB=E9=87=8D=E6=94=B9=E7=94=A8?=
 =?UTF-8?q?=E4=BB=A3=E8=A1=A8=E8=A1=8C=EF=BC=8C=E4=BF=AE=E5=A4=8D=20ONLY?=
 =?UTF-8?q?=5FFULL=5FGROUP=5FBY=20=E6=8A=A5=E9=94=99?=
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现象：小程序“药分享”页 onShow 抛
  TypeError: Cannot read properties of undefined (reading 'list')
根因在本接口：/yxe/yxe-share-detail/page?groupByProduct=true 返回
code=1 且不带 data，前端取 data.list 直接抛异常，中断整个 onShow。

原因：原 SQL 为 `SELECT a.* FROM yxe_share_detail a WHERE ... GROUP BY a.goods_name`。
MySQL 开启 ONLY_FULL_GROUP_BY 时，SELECT 列表中 a.* 的非分组列既不在
GROUP BY 内也不函数依赖于分组列，直接报
  Expression #1 of SELECT list is not in GROUP BY clause and contains
  nonaggregated column '...a.id' which is not functionally dependent on
  columns in GROUP BY clause
生产库恰好关闭了该 sql_mode 才长期未暴露，本地库（MySQL 9.7）已开启。

改法：取每个 goods_name 在**筛选结果集内**的最小 id 作为代表行，
语义与原 WHERE 之后 GROUP BY 一致。内层子查询重复同一套筛选条件，
否则按 province/city 过筛后该代表行可能不在结果集中，对应商品会整个消失。
未用窗口函数，不依赖 MySQL 8.0。

验证（本地库）：
- groupByProduct=true          code=0，5 个去重商品（修复前 code=1）
- groupByProduct + city        count=3，内外层条件一致生效
- groupByProduct + goodsName   count=2
- 不带 groupByProduct          count=12，原有行为不变
---
 .../yxe/mapper/xml/YxeShareDetailMapper.xml   | 77 ++++++++++++++++++-
 1 file changed, 73 insertions(+), 4 deletions(-)

diff --git a/src/main/java/com/gxwebsoft/yxe/mapper/xml/YxeShareDetailMapper.xml b/src/main/java/com/gxwebsoft/yxe/mapper/xml/YxeShareDetailMapper.xml
index 6553c7e..88f6601 100644
--- a/src/main/java/com/gxwebsoft/yxe/mapper/xml/YxeShareDetailMapper.xml
+++ b/src/main/java/com/gxwebsoft/yxe/mapper/xml/YxeShareDetailMapper.xml
@@ -2,7 +2,28 @@
 <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
 <mapper namespace="com.gxwebsoft.yxe.mapper.YxeShareDetailMapper">
 
-    <!-- 关联查询sql -->
+    <!--
+      关联查询sql
+
+      【按商品去重（groupByProduct）为什么不能用 GROUP BY】
+      原先写成 `SELECT a.* FROM yxe_share_detail a WHERE ... GROUP BY a.goods_name`。
+      MySQL 开启 ONLY_FULL_GROUP_BY 时，SELECT 列表 a.* 中的非分组列既不在
+      GROUP BY 中、也不函数依赖于分组列，会直接抛：
+        Expression #1 of SELECT list is not in GROUP BY clause and contains
+        nonaggregated column '...a.id' which is not functionally dependent on
+        columns in GROUP BY clause
+      接口因此返回 code=1 且**不带 data**，前端 getProductList 里 `data.list`
+      就抛 "Cannot read properties of undefined (reading 'list')"，
+      整个 onShow 中断，页面数据全部不渲染。
+
+      【现在的写法】
+      取每个 goods_name 在**筛选结果集内**的最小 id 作为代表行，语义与原先的
+      WHERE 之后 GROUP BY 完全一致（代表行只能从筛选后的行里产生）。
+      内层子查询必须重复同一套筛选条件：若只按整表取 MIN(id)，当 province/city
+      过筛后该代表行可能不在结果集中，对应商品会整个消失。
+
+      用 MIN(id) + IN 而非窗口函数，是因为不依赖 MySQL 8.0。
+    -->
     <sql id="selectSql">
         SELECT a.*
         FROM yxe_share_detail a
@@ -50,10 +71,58 @@
                 AND (a.comments LIKE CONCAT('%', #{param.keywords}, '%')
                 )
               </if>
+            <if test="param.groupByProduct != null">
+                AND a.id IN (
+                    SELECT MIN(b.id)
+                    FROM yxe_share_detail b
+                    WHERE 1 = 1
+                    <if test="param.id != null">
+                        AND b.id = #{param.id}
+                    </if>
+                    <if test="param.shareId != null">
+                        AND b.share_id = #{param.shareId}
+                    </if>
+                    <if test="param.province != null">
+                        AND b.province = #{param.province}
+                    </if>
+                    <if test="param.city != null">
+                        AND b.city = #{param.city}
+                    </if>
+                    <if test="param.goodsName != null">
+                        AND b.goods_name LIKE CONCAT('%', #{param.goodsName}, '%')
+                    </if>
+                    <if test="param.spec != null">
+                        AND b.spec LIKE CONCAT('%', #{param.spec}, '%')
+                    </if>
+                    <if test="param.num != null">
+                        AND b.num = #{param.num}
+                    </if>
+                    <if test="param.sortNumber != null">
+                        AND b.sort_number = #{param.sortNumber}
+                    </if>
+                    <if test="param.status != null">
+                        AND b.status = #{param.status}
+                    </if>
+                    <if test="param.deleted != null">
+                        AND b.deleted = #{param.deleted}
+                    </if>
+                    <if test="param.deleted == null">
+                        AND b.deleted = 0
+                    </if>
+                    <if test="param.createTimeStart != null">
+                        AND b.create_time &gt;= #{param.createTimeStart}
+                    </if>
+                    <if test="param.createTimeEnd != null">
+                        AND b.create_time &lt;= #{param.createTimeEnd}
+                    </if>
+                    <if test="param.keywords != null">
+                        AND (b.comments LIKE CONCAT('%', #{param.keywords}, '%')
+                        )
+                    </if>
+                    GROUP BY b.goods_name
+                )
+            </if>
         </where>
-        <if test="param.groupByProduct != null">
-            GROUP BY a.goods_name
-        </if>
     </sql>
 
     <!-- 分页查询 -->