您可以使用 Cloud Firestore 中的文本搜索功能搜索特定字符串 文档。
版本要求
文本搜索需要 Firestore 企业版数据库。
准备工作
如需执行文本搜索,您必须先 为需要搜索的字段创建文本索引 。
运行文本搜索
如需执行文本搜索,请在 search(...) 阶段的 query 参数中使用 documentMatches 表达式。
该操作仅在已使用文本索引编制索引的字段中进行搜索。如果有多个索引可用,Cloud Firestore 会选择一个 索引用于该操作。
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)
搜索完全匹配的字词
如需搜索完全匹配的字词,请将该字词用英文引号 (") 括起来:
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)
搜索字词组合
如需搜索字词组合(逻辑 AND),请用空格分隔字词:
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)
排除字词
如需排除字词,请在该字词前面添加连字符 (-):
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)
您还可以排除词组,例如 pizza -"New York"。
对结果排序
默认情况下,Cloud Firestore 按文档创建时间对结果进行排序,从最新到最旧。您可以改为按搜索得分排序,但这需要更多计算来计算和比较每个文档的准确得分:
如需按搜索得分对结果进行排序,请执行以下操作:
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();
向搜索阶段返回的文档添加字段
您可以使用 addFields 向搜索阶段返回的文档添加字段。返回由搜索阶段计算的值的表达式(如 score())可在搜索阶段的 addFields 中使用,以将这些值写入输出文档。
以下示例向搜索阶段返回的文档添加了得分字段:
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)