使用文字搜尋

使用 Cloud Firestore 中的文字搜尋功能,在文件中搜尋特定字串。

版本需求

Text Search 功能需要 Firestore Enterprise 版資料庫。

事前準備

如要執行 Text Search,您必須先為要搜尋的欄位建立文字索引。

如要執行 Text Search,請在 search(...) 階段的 query 參數中使用 documentMatches 運算式。

這項作業只會搜尋已建立文字索引的欄位。如果有多個索引可用,Cloud Firestore 會選取一個索引來執行作業。

Web

const result = await execute(db.pipeline().collection('restaurants')
  .search({
    query: documentMatches('waffles')
  }));
iOS
let snapshot = try await db.pipeline().collection("restaurants")
  .search(query: DocumentMatches("waffles"))
  .execute()

Kotlin

val pipeline = db.pipeline().collection("restaurants")
    .search(SearchStage.withQuery(documentMatches("waffles")))

Java

Pipeline pipeline = db.pipeline().collection("restaurants")
        .search(SearchStage.withQuery(documentMatches("waffles")));
Node.js
await db.pipeline().collection('restaurants')
  .search({
    query: documentMatches('waffles')
  })
  .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import DocumentMatches

results = (
    client.pipeline()
    .collection("restaurants")
    .search(DocumentMatches("waffles"))
    .execute()
)
Java
Pipeline.Snapshot results1 =
    firestore.pipeline().collection("restaurants")
        .search(Search.withQuery(documentMatches("waffles")))
        .execute().get();
Go
snapshot := client.Pipeline().
	Collection("restaurants").
	Search(firestore.WithSearchQuery(firestore.DocumentMatches("waffles"))).
	Execute(ctx)

搜尋完全相符的字詞

如要搜尋完全相符的字詞,請在字詞前後加上引號 ("):

Web

const result = await execute(db.pipeline().collection('restaurants')
  .search({
    query: documentMatches('"belgian waffles"')
  }));
iOS
let snapshot = try await db.pipeline().collection("restaurants")
  .search(query: DocumentMatches("\"belgian waffles\""))
  .execute()

Kotlin

val pipeline = db.pipeline().collection("restaurants")
    .search(SearchStage.withQuery(documentMatches("\"belgian waffles\"")))

Java

Pipeline pipeline = db.pipeline().collection("restaurants")
        .search(SearchStage.withQuery(documentMatches("\"belgian waffles\"")));
Node.js
await db.pipeline().collection('restaurants')
  .search({
    query: documentMatches('"belgian waffles"')
  })
  .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import DocumentMatches

results = (
    client.pipeline()
    .collection("restaurants")
    .search(DocumentMatches('"belgian waffles"'))
    .execute()
)
Java
Pipeline.Snapshot results2 =
    firestore.pipeline().collection("restaurants")
        .search(Search.withQuery(documentMatches("\"belgian waffles\"")))
        .execute().get();
Go
snapshot := client.Pipeline().
	Collection("restaurants").
	Search(firestore.WithSearchQuery(firestore.DocumentMatches("\"belgian waffles\""))).
	Execute(ctx)

搜尋字詞組合

如要搜尋字詞組合 (邏輯 AND),請以空格分隔字詞:

Web

const result = await execute(db.pipeline().collection('restaurants')
  .search({
    query: documentMatches('waffles eggs')
  }));
iOS
let snapshot = try await db.pipeline().collection("restaurants")
  .search(query: DocumentMatches("waffles eggs"))
  .execute()

Kotlin

val pipeline = db.pipeline().collection("restaurants")
    .search(SearchStage.withQuery(documentMatches("waffles eggs")))

Java

Pipeline pipeline = db.pipeline().collection("restaurants")
        .search(SearchStage.withQuery(documentMatches("waffles eggs")));
Node.js
await db.pipeline().collection('restaurants')
  .search({
    query: documentMatches('waffles eggs')
  })
  .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import DocumentMatches

results = (
    client.pipeline()
    .collection("restaurants")
    .search(DocumentMatches("waffles eggs"))
    .execute()
)
Java
firestore.collection("restaurants").add(new HashMap<String, Object>() {{
  put("name", "Morning Diner");
  put("description", "Start your day with waffles and eggs.");
}});
Pipeline.Snapshot results3 =
    firestore.pipeline().collection("restaurants")
        .search(Search.withQuery(documentMatches("waffles eggs")))
        .execute().get();
Go
snapshot := client.Pipeline().
	Collection("restaurants").
	Search(firestore.WithSearchQuery(firestore.DocumentMatches("waffles eggs"))).
	Execute(ctx)

排除字詞

如要排除某個字詞,請在該字詞前面加上連字號 (-):

Web

const result = await execute(db.pipeline().collection('restaurants')
  .search({
    query: documentMatches('coffee -waffles')
  }));
iOS
let snapshot = try await db.pipeline().collection("restaurants")
  .search(query: DocumentMatches("coffee -waffles"))
  .execute()

Kotlin

val pipeline = db.pipeline().collection("restaurants")
    .search(SearchStage.withQuery(documentMatches("waffles eggs")))

Java

Pipeline pipeline = db.pipeline().collection("restaurants")
        .search(SearchStage.withQuery(documentMatches("coffee -waffles")));
Node.js
await db.pipeline().collection('restaurants')
  .search({
    query: documentMatches('-waffles')
  })
  .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import DocumentMatches

results = (
    client.pipeline()
    .collection("restaurants")
    .search(DocumentMatches("-waffles"))
    .execute()
)
Java
firestore.collection("restaurants").add(new HashMap<String, Object>() {{
  put("name", "City Coffee");
  put("description", "Premium coffee and pastries.");
}});
Pipeline.Snapshot results4 =
    firestore.pipeline().collection("restaurants")
        .search(Search.withQuery(documentMatches("-waffles")))
        .execute().get();
Go
snapshot := client.Pipeline().
	Collection("restaurants").
	Search(firestore.WithSearchQuery(firestore.DocumentMatches("-waffles"))).
	Execute(ctx)

您也可以排除特定詞組,例如 pizza -"New York"。

結果排序方式

根據預設,Cloud Firestore 會依文件建立時間排序結果,由新到舊。您也可以改為依搜尋分數排序,但這需要更多運算資源,才能計算及比較每份文件的確切分數:

如要依搜尋分數排序結果,請按照下列步驟操作:

Web

const result = await execute(db.pipeline().collection('restaurants')
  .search({
    query: documentMatches('waffles'),
    sort: score().descending()
  }));
iOS
let snapshot = try await db.pipeline().collection("restaurants")
  .search(
      query: DocumentMatches("waffles"),
      sort: [Score().descending()]
      )
  .execute()

Kotlin

val pipeline = db.pipeline().collection("restaurants")
    .search(SearchStage
              .withQuery(documentMatches("waffles"))
              .withSort(score().descending())
              )
Node.js
await db.pipeline().collection('restaurants')
  .search({
    query: documentMatches('waffles'),
    sort: score().descending()
  })
  .execute();

在搜尋階段傳回的文件中新增欄位

您可以使用 addFields,將欄位新增至搜尋階段傳回的文件。傳回搜尋階段計算值的運算式 (例如 score()),可在搜尋階段的 addFields 中使用,將這些值寫入輸出文件。

以下範例會將分數欄位新增至搜尋階段傳回的文件:

Web

const result = await execute(db.pipeline().collection('restaurants')
  .search({
    query: 'menu:waffles',
    addFields: [
        score().as('score'),
    ]
  }));
iOS
let snapshot = try await db.pipeline().collection("restaurants")
  .search(
    query: DocumentMatches("waffles"),
    addFields: [
      Score().as("score")
    ]
  )
  .execute()

Kotlin

val pipeline = db.pipeline().collection("restaurants")
    .search(SearchStage.withQuery(documentMatches("waffles eggs")))

Java

Pipeline pipeline = db.pipeline().collection("restaurants")
        .search(
                SearchStage.withQuery(documentMatches("menu:waffles"))
                        .withAddFields(score().alias("score")));
Node.js
await db.pipeline().collection('restaurants')
  .search({
    query: field('menu').matches('waffles'),
    addFields: [
        score().as('score'),
    ]
  }).execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import DocumentMatches, Score
from google.cloud.firestore_v1.pipeline_stages import SearchOptions

results = (
    client.pipeline()
    .collection("restaurants")
    .search(
        SearchOptions(
            query=DocumentMatches("menu:waffles"),
            add_fields=[Score().as_("score")],
        )
    )
    .execute()
)
Java
Pipeline.Snapshot results5 =
    firestore.pipeline().collection("restaurants")
        .search(Search.withQuery(field("menu").regexMatch("waffles"))
            .withAddFields(score().as("score")))
        .execute().get();
Go
snapshot := client.Pipeline().
	Collection("restaurants").
	Search(
		firestore.WithSearchQuery(firestore.FieldOf("menu").RegexMatch("waffles")),
		firestore.WithSearchAddFields(firestore.Score().As("score")),
	).
	Execute(ctx)