查询扩展

查询扩展是指在最初未找到任何结果或找到的结果太少时，逐步放宽查询约束条件，以包含更多结果。这会导致调整每个查询的结果大小。

教程：查询扩展

本教程介绍了如何启用查询扩展功能。如果买家使用模糊的搜索字词或多字词搜索字词，则可能会收到空响应。启用查询扩展后，系统会分析请求，并根据解析的搜索查询返回展开后的商品列表。

---

如需遵循有关此任务的分步指导，请直接在 Cloud Shell Editor 中点击操作演示：

操作演示

---

示例数据集

本页以下面的数据集为例。仅包含说明所需的字段。

商品数据集示例

ID	title	brands	categories	price_info.price
"nest_mini_2nd_gen"	"Nest Mini (2nd gen)"	["Google", "Nest"]	["Nest > speakers and displays"]	49.00
"nest_audio"	"Nest Audio"	["Google", "Nest"]	["Nest > speakers and displays"]	99.99
"nest_hub_max"	"Nest Hub Max"	["Google", "Nest"]	["Nest > speakers and displays"]	229.00
"nest_hub"	"Nest Hub"	["Google", "Nest"]	["Nest > speakers and displays"]	88.99
"google_home_max"	"Google Home Max"	["Google", "Nest"]	["Nest > speakers and displays"]	299.00
"google_home_mini"	"Google Home Mini"	["Google", "Nest"]	["Nest > speakers and displays"]	49.00
"google_pixel_5"	"Google Pixel 5"	["Google", "Pixel"]	["Pixel > phones"]	699.00
"google_pixel_4a_with_5g"	"Google Pixel 4a with 5G"	["Google", "Pixel"]	["Pixel > phones"]	499.00
"google_pixel_4a"	"Google Pixel 4a Phones"	["Google", "Pixel"]	["Pixel > phones"]	349.00
"google_pixel_stand"	"Google Pixel Stand"	["Google", "Pixel"]	["Pixel > featured accessories"]	79.00
"google_pixel_buds"	"Google Pixel Buds"	["Google", "Pixel"]	["Pixel > featured accessories"]	179.00
"google_pixel_5_case"	"Google Pixel 5 Case"	["Google", "Pixel"]	["Pixel > featured accessories"]	40.00
"google_pixel_4a_5g_case"	"Google Pixel 4a (5G) Case"	["Google", "Pixel"]	["Pixel > featured accessories"]	40.00
"google_pixel_4a_case"	"Google Pixel 4a Case"	["Google", "Pixel"]	["Pixel > featured accessories"]	40.00

查询扩展

查询扩展会增加查询字词的召回率，但结果很少，尤其是长尾查询。

Java

import com.google.cloud.retail.v2.SearchRequest;
import com.google.cloud.retail.v2.SearchRequest.QueryExpansionSpec;
import com.google.cloud.retail.v2.SearchRequest.QueryExpansionSpec.Condition;
import com.google.cloud.retail.v2.SearchResponse;
import com.google.cloud.retail.v2.SearchServiceClient;

public static void searchProductsWithQueryExpansion(String query, int pageSize,
    Condition condition) throws IOException, InterruptedException {
  QueryExpansionSpec queryExpansionSpec = QueryExpansionSpec.newBuilder()
      .setCondition(condition)
      .build();

  SearchRequest searchRequest = SearchRequest.newBuilder()
      .setPlacement(DEFAULT_SEARCH_PLACEMENT_NAME)
      .setBranch(DEFAULT_BRANCH_NAME)
      .setVisitorId(VISITOR_ID)
      .setQuery(query)
      .setPageSize(pageSize)
      .setQueryExpansionSpec(queryExpansionSpec)
      .build();

  try (SearchServiceClient searchClient = SearchServiceClient.create()) {
    SearchResponse response = searchClient.search(searchRequest).getPage().getResponse();
    System.out.println("Search response: " + searchResponse);
  }
}

例如，如果您在未进行查询扩展的情况下搜索“Google Pixel 5”，您可能只会在结果中看到“google_pixel_5”。而使用查询扩展时，您可能会收到“google_pixel_4a_with_5g”、“google_pixel_4a”和“google_pixel_5_case”。