共计 5558 个字符，预计需要花费 14 分钟才能阅读完成。
有这样一个带有搜寻性能的用户界面需要：
搜寻流程如下所示：
这个需要波及两个实体：
- “评分（Rating）、用户名（Username）”数据与
User实体相干 - “创立日期（create date）、观看次数（number of views）、题目（title）、注释（body）”与
Story实体相干
须要反对的性能对 User 实体中的评分（Rating）的频繁批改以及下列搜寻性能：
- 按 User 评分进行范畴搜寻
- 按 Story 创立日期进行范畴搜寻
- 按 Story 浏览量进行范畴搜寻
- 按 Story 题目进行全文搜寻
- 按 Story 注释进行全文搜寻
Postgres 中创立表构造和索引
创立 users 表和 stories 表以及对应搜寻需要相干的索引，包含：
- 应用 btree 索引来反对按 User 评分搜寻
- 应用 btree 索引来反对按 Story 创立日期、查看次数的搜寻
- 应用 gin 索引来反对全文搜寻内容（同时创立全文搜寻列
fulltext，类型应用tsvector以反对全文搜寻）
具体创立脚本如下：
--Create Users table
CREATE TABLE IF NOT EXISTS users
(
id bigserial NOT NULL,
name character varying(100) NOT NULL,
rating integer,
PRIMARY KEY (id)
)
;
CREATE INDEX usr_rating_idx
ON users USING btree
(rating ASC NULLS LAST)
TABLESPACE pg_default
;
--Create Stories table
CREATE TABLE IF NOT EXISTS stories
(
id bigserial NOT NULL,
create_date timestamp without time zone NOT NULL,
num_views bigint NOT NULL,
title text NOT NULL,
body text NOT NULL,
fulltext tsvector,
user_id bigint,
PRIMARY KEY (id),
CONSTRAINT user_id_fk FOREIGN KEY (user_id)
REFERENCES users (id) MATCH SIMPLE
ON UPDATE NO ACTION
ON DELETE NO ACTION
NOT VALID
)
;
CREATE INDEX str_bt_idx
ON stories USING btree
(create_date ASC NULLS LAST,
num_views ASC NULLS LAST, user_id ASC NULLS LAST)
;
CREATE INDEX fulltext_search_idx
ON stories USING gin
(fulltext)
;创立 Spring Boot 利用
- 我的项目依赖关系（这里应用 Gradle 构建）：
plugins {
id 'java'
id 'org.springframework.boot' version '3.1.3'
id 'io.spring.dependency-management' version '1.1.3'
}
group = 'com.example'
version = '0.0.1-SNAPSHOT'
java {sourceCompatibility = '17'}
repositories {mavenCentral()
}
dependencies {
implementation 'org.springframework.boot:spring-boot-starter-data-jdbc'
implementation 'org.springframework.boot:spring-boot-starter-web'
runtimeOnly 'org.postgresql:postgresql'
testImplementation 'org.springframework.boot:spring-boot-starter-test'
}
tasks.named('test') {useJUnitPlatform()
}application.yaml中配置数据库连贯信息
spring:
datasource:
url: jdbc:postgresql://localhost:5432/postgres
username: postgres
password: postgres- 数据模型
定义须要用到的各种数据模型：
public record Period(String fieldName, LocalDateTime min, LocalDateTime max) {
}
public record Range(String fieldName, long min, long max) {
}
public record Search(List<Period> periods, List<Range> ranges, String fullText, long offset, long limit) {
}
public record UserStory(Long id, LocalDateTime createDate, Long numberOfViews,
String title, String body, Long userRating, String userName, Long userId) {}这里应用 Java 16 推出的新个性 record 实现，所以代码十分简洁。如果您还不理解的话，能够返回程序猿 DD 的 Java 新个性专栏补全一下知识点。
- 数据拜访（Repository）
@Repository
public class UserStoryRepository {
private final JdbcTemplate jdbcTemplate;
@Autowired
public UserStoryRepository(JdbcTemplate jdbcTemplate) {this.jdbcTemplate = jdbcTemplate;}
public List<UserStory> findByFilters(Search search) {
return jdbcTemplate.query(
"""
SELECT s.id id, create_date, num_views,
title, body, user_id, name user_name,
rating user_rating
FROM stories s INNER JOIN users u
ON s.user_id = u.id
WHERE true
""" + buildDynamicFiltersText(search)
+ "order by create_date desc offset ? limit ?",
(rs, rowNum) -> new UserStory(rs.getLong("id"),
rs.getTimestamp("create_date").toLocalDateTime(),
rs.getLong("num_views"),
rs.getString("title"),
rs.getString("body"),
rs.getLong("user_rating"),
rs.getString("user_name"),
rs.getLong("user_id")
),
buildDynamicFilters(search)
);
}
public void save(UserStory userStory) {var keyHolder = new GeneratedKeyHolder();
jdbcTemplate.update(connection -> {
PreparedStatement ps = connection
.prepareStatement(
"""
INSERT INTO stories (create_date, num_views, title, body, user_id)
VALUES (?, ?, ?, ?, ?)
""",
Statement.RETURN_GENERATED_KEYS
);
ps.setTimestamp(1, Timestamp.valueOf(userStory.createDate()));
ps.setLong(2, userStory.numberOfViews());
ps.setString(3, userStory.title());
ps.setString(4, userStory.body());
ps.setLong(5, userStory.userId());
return ps;
}, keyHolder);
var generatedId = (Long) keyHolder.getKeys().get("id");
if (generatedId != null) {updateFullTextField(generatedId);
}
}
private void updateFullTextField(Long generatedId) {
jdbcTemplate.update("""UPDATE stories SET fulltext = to_tsvector(title ||' ' || body)
where id = ?
""",
generatedId
);
}
private Object[] buildDynamicFilters(Search search) {var filtersStream = search.ranges().stream()
.flatMap(range -> Stream.of((Object) range.min(), range.max())
);
var periodsStream = search.periods().stream()
.flatMap(range -> Stream.of((Object) Timestamp.valueOf(range.min()), Timestamp.valueOf(range.max()))
);
filtersStream = Stream.concat(filtersStream, periodsStream);
if (!search.fullText().isBlank()) {filtersStream = Stream.concat(filtersStream, Stream.of(search.fullText()));
}
filtersStream = Stream.concat(filtersStream, Stream.of(search.offset(), search.limit()));
return filtersStream.toArray();}
private String buildDynamicFiltersText(Search search) {
var rangesFilterString =
Stream.concat(search.ranges()
.stream()
.map(range -> String.format("and %s between ? and ?", range.fieldName())
),
search.periods()
.stream()
.map(range -> String.format("and %s between ? and ?", range.fieldName())
)
)
.collect(Collectors.joining(" "));
return rangesFilterString + buildFulltextFilterText(search.fullText());
}
private String buildFulltextFilterText(String fullText) {return fullText.isBlank() ? "":" and fulltext @@ plainto_tsquery(?) ";
}
}- Controller 实现
@RestController
@RequestMapping("/user-stories")
public class UserStoryController {
private final UserStoryRepository userStoryRepository;
@Autowired
public UserStoryController(UserStoryRepository userStoryRepository) {this.userStoryRepository = userStoryRepository;}
@PostMapping
public void save(@RequestBody UserStory userStory) {userStoryRepository.save(userStory);
}
@PostMapping("/search")
public List<UserStory> search(@RequestBody Search search) {return userStoryRepository.findByFilters(search);
}
}小结
本文介绍了如何在 Spring Boot 中联合 Postgres 数据库实现全文搜寻的性能，该办法比起应用 Elasticsearch 更为轻量级，非常适合一些小我的项目场景应用。心愿本文内容对您有所帮忙。如果您学习过程中如遇艰难？能够退出咱们超高品质的 Spring 技术交换群，参加交换与探讨，更好的学习与提高！更多 Spring Boot 教程能够点击中转！，欢送珍藏与转发反对！
参考资料
- Postgres full-text search Spring boot integration
- Java 16 新个性：record
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