行转列 显示table 笔记

要显示成这样：

用前端reduce的方式
        this.tableDataSell = dd.reduce((acc, item) => {
          let category = acc.find((entry) => entry.categoryName === item.categoryName);
          if (!category) {
            category = { categoryName: item.categoryName };
            acc.push(category);
          }
          category[item.periodDay] = item.quantity;
          return acc;
        }, []);

// el-table 展示多个列

  <el-table class="custom-table" :data="tableDataSell">
            <el-table-column label="类别" align="center" prop="categoryName"/>

            <el-table-column
              v-for="date in dateList"
              :key="date"
              :label="date"
              :prop="date">
            </el-table-column>
          </el-table>