Question

使用下面显示的示例json，我试图检索包含至少一个类别的所有文档，这些类别是包含在下面的的数组对象，其文本值为＆＃39; drink＆＃39;使用以下查询但返回的结果为空。有人可以帮助我做到这一点吗？

SELECT items.id ,items.description ,items.Categories FROM items WHERE ARRAY_CONTAINS(items.Categories.Category.Text, "drink")

＆＃13;
＆＃13;
{ "id": "1dbaf1d0-6549-11a0-88a8-001256957023", "Categories": { "Category": [{ "Type": "GS1", "Id": "10000266", "Text": "Stimulants/Energy Drinks Ready to Drink" }, { "Type": "GS2", "Id": "10000266", "Text": "Healthy Drink" }] } },
＆＃13;
＆＃13;
＆＃13; 注意：json有点让对象本身包裹数组 - 这个json是从XML转换而来的结果。所以请假设我无法控制如何将此对象保存为json

Answer 1

您需要在查询中展平文档，以通过将数组加入主文档来获得所需的结果。您想要的查询如下所示：

SELECT items.id, items.Categories
FROM items
JOIN Category IN items.Categories.Category
WHERE CONTAINS(LOWER(Category.Text), "drink")

但是，由于没有DISTINCT查询的概念，这将产生与包含单词“drink”的Category项目数相等的重复项。因此，此查询将生成两次示例文档：

[
  {
    "id": "1dbaf1d0-6549-11a0-88a8-001256957023",
    "Categories": {
      "Category": [
        {
          "Type": "GS1",
          "Id": "10000266",
          "Text": "Stimulants/Energy Drinks Ready to Drink"
        },
        {
          "Type": "GS2",
          "Id": "10000266",
          "Text": "Healthy Drink"
        }
      ]
    }
  },
  {
    "id": "1dbaf1d0-6549-11a0-88a8-001256957023",
    "Categories": {
      "Category": [
        {
          "Type": "GS1",
          "Id": "10000266",
          "Text": "Stimulants/Energy Drinks Ready to Drink"
        },
        {
          "Type": "GS2",
          "Id": "10000266",
          "Text": "Healthy Drink"
        }
      ]
    }
  }
]

如果“类别”数组中包含大量具有“饮料”的类别项目，则可能会出现问题且成本高昂。

如果您只对单个类别感兴趣，可以通过将查询更改为：

来减少这种情况

SELECT items.id, Category
FROM items
JOIN Category IN items.Categories.Category
WHERE CONTAINS(LOWER(Category.Text), "drink")

这会产生更简洁的结果，只有重复的id字段，每个匹配的Category项目都会出现一次：

  [{
    "id": "1dbaf1d0-6549-11a0-88a8-001256957023",
    "Category": {
      "Type": "GS1",
      "Id": "10000266",
      "Text": "Stimulants/Energy Drinks Ready to Drink"
    }
  },
  {
    "id": "1dbaf1d0-6549-11a0-88a8-001256957023",
    "Category": {
      "Type": "GS2",
      "Id": "10000266",
      "Text": "Healthy Drink"
    }
  }]

否则，当您从查询中取回结果以删除重复文档时，您必须过滤结果。

Answer 2

如果是我和我正在构建具有此要求的生产系统，我将使用Azure搜索。 Here是关于将它连接到DocumentDB的一些信息。

如果您不想这样做，我们必须忍受不能改变文档形状的约束，我能想到的唯一方法是使用用户定义函数（UDF）像这样：

   /**
     * Created by Talisson on 03-04-2016.
     */

public class ViewPagerAdapter extends FragmentStatePagerAdapter {

    CharSequence Titles[]; // This will Store the Titles of the Tabs which are Going to be passed when ViewPagerAdapter is created
    int NumbOfTabs; // Store the number of tabs, this will also be passed when the ViewPagerAdapter is created


    // Build a Constructor and assign the passed Values to appropriate values in the class
    public ViewPagerAdapter(FragmentManager fm,CharSequence mTitles[], int mNumbOfTabsumb) {
        super(fm);

        this.Titles = mTitles;
        this.NumbOfTabs = mNumbOfTabsumb;

    }

    @Override
    public void destroyItem(ViewGroup container, int position, Object object) {
        super.destroyItem(container, position, object);
        FragmentManager manager = ((Fragment) object).getFragmentManager();
        FragmentTransaction trans = manager.beginTransaction();
        trans.remove((Fragment) object);
        trans.commit();
    }



    //This method return the fragment for the every position in the View Pager
    @Override
    public Fragment getItem(int position) {

        switch(position) {// if the position is 0 we are returning the First tab
            case 0:
            Tab1 tab1 = new Tab1();
            return tab1;
            case 1:
            Tab2 tab2 = new Tab2();
            return tab2;
            case 2:
            Tab3 tab3 = new Tab3();
            return tab3;
            default:
                return null;
        }


    }

    // This method return the titles for the Tabs in the Tab Strip

    @Override
    public CharSequence getPageTitle(int position) {
        return Titles[position];
    }

    // This method return the Number of tabs for the tabs Strip

    @Override
    public int getCount() {
        return NumbOfTabs;
    }
}

请注意，上面的代码在实际尝试之后被提问者修改，所以它经过了一些测试。

您可以将其用于以下查询：

function GetItemsWithMatchingCategories(categories, matchingString) {
  if (Array.isArray(categories) && categories !== null) {
    var lowerMatchingString = matchingString.toLowerCase();
    for (var index = 0; index < categories.length; index++) {
      var category = categories[index];
      var categoryName = category.Text.toLowerCase();
      if (categoryName.indexOf(lowerMatchingString) >= 0) {
        return true;
      }
    }
  }
}

另请注意，这将导致全表扫描（除非您可以将其与可以使用索引的其他条件结合使用），这可能会或可能不会满足您的性能/ RU限制约束。

文档Db查询过滤器包含数组的属性

2 个答案: