示例 - 索引和查询JSON文档

学习如何使用Redis查询引擎与JSON

此示例展示了如何为JSON数据创建搜索索引并针对该索引运行查询。

确保你已经安装了Redis Stack和Jedis。

首先导入依赖项：

Java-Sync

import redis.clients.jedis.UnifiedJedis;
import redis.clients.jedis.exceptions.JedisDataException;
import redis.clients.jedis.json.Path2;
import redis.clients.jedis.search.*;
import redis.clients.jedis.search.aggr.*;
import redis.clients.jedis.search.schemafields.*;
import org.json.JSONObject;
import java.util.List;

public class HomeJsonExample {
    public void run() {
        UnifiedJedis jedis = new UnifiedJedis("redis://localhost:6379");

        JSONObject user1 = new JSONObject()
                .put("name", "Paul John")
                .put("email", "paul.john@example.com")
                .put("age", 42)
                .put("city", "London");
        
        JSONObject user2 = new JSONObject()
                .put("name", "Eden Zamir")
                .put("email", "eden.zamir@example.com")
                .put("age", 29)
                .put("city", "Tel Aviv");
        
        JSONObject user3 = new JSONObject()
                .put("name", "Paul Zamir")
                .put("email", "paul.zamir@example.com")
                .put("age", 35)
                .put("city", "Tel Aviv");

        SchemaField[] schema = {
            TextField.of("$.name").as("name"),
            TextField.of("$.city").as("city"),
            NumericField.of("$.age").as("age")
        };

        String createResult = jedis.ftCreate("idx:users",
            FTCreateParams.createParams()
                .on(IndexDataType.JSON)
                .addPrefix("user:"),
                schema
        );

        System.out.println(createResult); // >>> OK

        String user1Set = jedis.jsonSet("user:1", new Path2("$"), user1);
        String user2Set = jedis.jsonSet("user:2", new Path2("$"), user2);
        String user3Set = jedis.jsonSet("user:3", new Path2("$"), user3);

        SearchResult findPaulResult = jedis.ftSearch("idx:users",
             "Paul @age:[30 40]"
        );
        
        System.out.println(findPaulResult.getTotalResults()); // >>> 1

        List<Document> paulDocs = findPaulResult.getDocuments();

        for (Document doc: paulDocs) {
            System.out.println(doc.getId());
        }
        // >>> user:3

        SearchResult citiesResult = jedis.ftSearch("idx:users",
            "Paul",
            FTSearchParams.searchParams()
                .returnFields("city")
        );

        System.out.println(citiesResult.getTotalResults()); // >>> 2

        for (Document doc: citiesResult.getDocuments()) {
            System.out.println(doc.getId());
        }
        // >>> user:1
        // >>> user:3

        AggregationResult aggResult = jedis.ftAggregate("idx:users",
            new AggregationBuilder("*")
                .groupBy("@city", Reducers.count().as("count"))
        );

        System.out.println(aggResult.getTotalResults()); // >>> 2

        for (Row cityRow: aggResult.getRows()) {
            System.out.println(String.format(
                "%s - %d",
                cityRow.getString("city"), cityRow.getLong("count"))
            );
        }
        // >>> London - 1
        // >>> Tel Aviv - 2

        jedis.close();
    }
}

连接到数据库：

Java-Sync

import redis.clients.jedis.UnifiedJedis;
import redis.clients.jedis.exceptions.JedisDataException;
import redis.clients.jedis.json.Path2;
import redis.clients.jedis.search.*;
import redis.clients.jedis.search.aggr.*;
import redis.clients.jedis.search.schemafields.*;
import org.json.JSONObject;
import java.util.List;

public class HomeJsonExample {
    public void run() {
        UnifiedJedis jedis = new UnifiedJedis("redis://localhost:6379");

        JSONObject user1 = new JSONObject()
                .put("name", "Paul John")
                .put("email", "paul.john@example.com")
                .put("age", 42)
                .put("city", "London");
        
        JSONObject user2 = new JSONObject()
                .put("name", "Eden Zamir")
                .put("email", "eden.zamir@example.com")
                .put("age", 29)
                .put("city", "Tel Aviv");
        
        JSONObject user3 = new JSONObject()
                .put("name", "Paul Zamir")
                .put("email", "paul.zamir@example.com")
                .put("age", 35)
                .put("city", "Tel Aviv");

        SchemaField[] schema = {
            TextField.of("$.name").as("name"),
            TextField.of("$.city").as("city"),
            NumericField.of("$.age").as("age")
        };

        String createResult = jedis.ftCreate("idx:users",
            FTCreateParams.createParams()
                .on(IndexDataType.JSON)
                .addPrefix("user:"),
                schema
        );

        System.out.println(createResult); // >>> OK

        String user1Set = jedis.jsonSet("user:1", new Path2("$"), user1);
        String user2Set = jedis.jsonSet("user:2", new Path2("$"), user2);
        String user3Set = jedis.jsonSet("user:3", new Path2("$"), user3);

        SearchResult findPaulResult = jedis.ftSearch("idx:users",
             "Paul @age:[30 40]"
        );
        
        System.out.println(findPaulResult.getTotalResults()); // >>> 1

        List<Document> paulDocs = findPaulResult.getDocuments();

        for (Document doc: paulDocs) {
            System.out.println(doc.getId());
        }
        // >>> user:3

        SearchResult citiesResult = jedis.ftSearch("idx:users",
            "Paul",
            FTSearchParams.searchParams()
                .returnFields("city")
        );

        System.out.println(citiesResult.getTotalResults()); // >>> 2

        for (Document doc: citiesResult.getDocuments()) {
            System.out.println(doc.getId());
        }
        // >>> user:1
        // >>> user:3

        AggregationResult aggResult = jedis.ftAggregate("idx:users",
            new AggregationBuilder("*")
                .groupBy("@city", Reducers.count().as("count"))
        );

        System.out.println(aggResult.getTotalResults()); // >>> 2

        for (Row cityRow: aggResult.getRows()) {
            System.out.println(String.format(
                "%s - %d",
                cityRow.getString("city"), cityRow.getLong("count"))
            );
        }
        // >>> London - 1
        // >>> Tel Aviv - 2

        jedis.close();
    }
}

创建一些测试数据以添加到数据库中：

Java-Sync

import redis.clients.jedis.UnifiedJedis;
import redis.clients.jedis.exceptions.JedisDataException;
import redis.clients.jedis.json.Path2;
import redis.clients.jedis.search.*;
import redis.clients.jedis.search.aggr.*;
import redis.clients.jedis.search.schemafields.*;
import org.json.JSONObject;
import java.util.List;

public class HomeJsonExample {
    public void run() {
        UnifiedJedis jedis = new UnifiedJedis("redis://localhost:6379");

        JSONObject user1 = new JSONObject()
                .put("name", "Paul John")
                .put("email", "paul.john@example.com")
                .put("age", 42)
                .put("city", "London");
        
        JSONObject user2 = new JSONObject()
                .put("name", "Eden Zamir")
                .put("email", "eden.zamir@example.com")
                .put("age", 29)
                .put("city", "Tel Aviv");
        
        JSONObject user3 = new JSONObject()
                .put("name", "Paul Zamir")
                .put("email", "paul.zamir@example.com")
                .put("age", 35)
                .put("city", "Tel Aviv");

        SchemaField[] schema = {
            TextField.of("$.name").as("name"),
            TextField.of("$.city").as("city"),
            NumericField.of("$.age").as("age")
        };

        String createResult = jedis.ftCreate("idx:users",
            FTCreateParams.createParams()
                .on(IndexDataType.JSON)
                .addPrefix("user:"),
                schema
        );

        System.out.println(createResult); // >>> OK

        String user1Set = jedis.jsonSet("user:1", new Path2("$"), user1);
        String user2Set = jedis.jsonSet("user:2", new Path2("$"), user2);
        String user3Set = jedis.jsonSet("user:3", new Path2("$"), user3);

        SearchResult findPaulResult = jedis.ftSearch("idx:users",
             "Paul @age:[30 40]"
        );
        
        System.out.println(findPaulResult.getTotalResults()); // >>> 1

        List<Document> paulDocs = findPaulResult.getDocuments();

        for (Document doc: paulDocs) {
            System.out.println(doc.getId());
        }
        // >>> user:3

        SearchResult citiesResult = jedis.ftSearch("idx:users",
            "Paul",
            FTSearchParams.searchParams()
                .returnFields("city")
        );

        System.out.println(citiesResult.getTotalResults()); // >>> 2

        for (Document doc: citiesResult.getDocuments()) {
            System.out.println(doc.getId());
        }
        // >>> user:1
        // >>> user:3

        AggregationResult aggResult = jedis.ftAggregate("idx:users",
            new AggregationBuilder("*")
                .groupBy("@city", Reducers.count().as("count"))
        );

        System.out.println(aggResult.getTotalResults()); // >>> 2

        for (Row cityRow: aggResult.getRows()) {
            System.out.println(String.format(
                "%s - %d",
                cityRow.getString("city"), cityRow.getLong("count"))
            );
        }
        // >>> London - 1
        // >>> Tel Aviv - 2

        jedis.close();
    }
}

创建一个索引。在这个例子中，只有带有键前缀 user: 的 JSON 文档会被索引。更多信息，请参阅查询语法。

Java-Sync

import redis.clients.jedis.UnifiedJedis;
import redis.clients.jedis.exceptions.JedisDataException;
import redis.clients.jedis.json.Path2;
import redis.clients.jedis.search.*;
import redis.clients.jedis.search.aggr.*;
import redis.clients.jedis.search.schemafields.*;
import org.json.JSONObject;
import java.util.List;

public class HomeJsonExample {
    public void run() {
        UnifiedJedis jedis = new UnifiedJedis("redis://localhost:6379");

        JSONObject user1 = new JSONObject()
                .put("name", "Paul John")
                .put("email", "paul.john@example.com")
                .put("age", 42)
                .put("city", "London");
        
        JSONObject user2 = new JSONObject()
                .put("name", "Eden Zamir")
                .put("email", "eden.zamir@example.com")
                .put("age", 29)
                .put("city", "Tel Aviv");
        
        JSONObject user3 = new JSONObject()
                .put("name", "Paul Zamir")
                .put("email", "paul.zamir@example.com")
                .put("age", 35)
                .put("city", "Tel Aviv");

        SchemaField[] schema = {
            TextField.of("$.name").as("name"),
            TextField.of("$.city").as("city"),
            NumericField.of("$.age").as("age")
        };

        String createResult = jedis.ftCreate("idx:users",
            FTCreateParams.createParams()
                .on(IndexDataType.JSON)
                .addPrefix("user:"),
                schema
        );

        System.out.println(createResult); // >>> OK

        String user1Set = jedis.jsonSet("user:1", new Path2("$"), user1);
        String user2Set = jedis.jsonSet("user:2", new Path2("$"), user2);
        String user3Set = jedis.jsonSet("user:3", new Path2("$"), user3);

        SearchResult findPaulResult = jedis.ftSearch("idx:users",
             "Paul @age:[30 40]"
        );
        
        System.out.println(findPaulResult.getTotalResults()); // >>> 1

        List<Document> paulDocs = findPaulResult.getDocuments();

        for (Document doc: paulDocs) {
            System.out.println(doc.getId());
        }
        // >>> user:3

        SearchResult citiesResult = jedis.ftSearch("idx:users",
            "Paul",
            FTSearchParams.searchParams()
                .returnFields("city")
        );

        System.out.println(citiesResult.getTotalResults()); // >>> 2

        for (Document doc: citiesResult.getDocuments()) {
            System.out.println(doc.getId());
        }
        // >>> user:1
        // >>> user:3

        AggregationResult aggResult = jedis.ftAggregate("idx:users",
            new AggregationBuilder("*")
                .groupBy("@city", Reducers.count().as("count"))
        );

        System.out.println(aggResult.getTotalResults()); // >>> 2

        for (Row cityRow: aggResult.getRows()) {
            System.out.println(String.format(
                "%s - %d",
                cityRow.getString("city"), cityRow.getLong("count"))
            );
        }
        // >>> London - 1
        // >>> Tel Aviv - 2

        jedis.close();
    }
}

将三组用户数据作为JSON对象添加到数据库中。如果你使用带有user:前缀的键，那么Redis会在你添加时自动索引这些对象：

Java-Sync

import redis.clients.jedis.UnifiedJedis;
import redis.clients.jedis.exceptions.JedisDataException;
import redis.clients.jedis.json.Path2;
import redis.clients.jedis.search.*;
import redis.clients.jedis.search.aggr.*;
import redis.clients.jedis.search.schemafields.*;
import org.json.JSONObject;
import java.util.List;

public class HomeJsonExample {
    public void run() {
        UnifiedJedis jedis = new UnifiedJedis("redis://localhost:6379");

        JSONObject user1 = new JSONObject()
                .put("name", "Paul John")
                .put("email", "paul.john@example.com")
                .put("age", 42)
                .put("city", "London");
        
        JSONObject user2 = new JSONObject()
                .put("name", "Eden Zamir")
                .put("email", "eden.zamir@example.com")
                .put("age", 29)
                .put("city", "Tel Aviv");
        
        JSONObject user3 = new JSONObject()
                .put("name", "Paul Zamir")
                .put("email", "paul.zamir@example.com")
                .put("age", 35)
                .put("city", "Tel Aviv");

        SchemaField[] schema = {
            TextField.of("$.name").as("name"),
            TextField.of("$.city").as("city"),
            NumericField.of("$.age").as("age")
        };

        String createResult = jedis.ftCreate("idx:users",
            FTCreateParams.createParams()
                .on(IndexDataType.JSON)
                .addPrefix("user:"),
                schema
        );

        System.out.println(createResult); // >>> OK

        String user1Set = jedis.jsonSet("user:1", new Path2("$"), user1);
        String user2Set = jedis.jsonSet("user:2", new Path2("$"), user2);
        String user3Set = jedis.jsonSet("user:3", new Path2("$"), user3);

        SearchResult findPaulResult = jedis.ftSearch("idx:users",
             "Paul @age:[30 40]"
        );
        
        System.out.println(findPaulResult.getTotalResults()); // >>> 1

        List<Document> paulDocs = findPaulResult.getDocuments();

        for (Document doc: paulDocs) {
            System.out.println(doc.getId());
        }
        // >>> user:3

        SearchResult citiesResult = jedis.ftSearch("idx:users",
            "Paul",
            FTSearchParams.searchParams()
                .returnFields("city")
        );

        System.out.println(citiesResult.getTotalResults()); // >>> 2

        for (Document doc: citiesResult.getDocuments()) {
            System.out.println(doc.getId());
        }
        // >>> user:1
        // >>> user:3

        AggregationResult aggResult = jedis.ftAggregate("idx:users",
            new AggregationBuilder("*")
                .groupBy("@city", Reducers.count().as("count"))
        );

        System.out.println(aggResult.getTotalResults()); // >>> 2

        for (Row cityRow: aggResult.getRows()) {
            System.out.println(String.format(
                "%s - %d",
                cityRow.getString("city"), cityRow.getLong("count"))
            );
        }
        // >>> London - 1
        // >>> Tel Aviv - 2

        jedis.close();
    }
}

你现在可以使用索引来搜索JSON对象。下面的查询搜索在任何字段中包含文本“Paul”并且 age值在30到40之间的对象：

Java-Sync

import redis.clients.jedis.UnifiedJedis;
import redis.clients.jedis.exceptions.JedisDataException;
import redis.clients.jedis.json.Path2;
import redis.clients.jedis.search.*;
import redis.clients.jedis.search.aggr.*;
import redis.clients.jedis.search.schemafields.*;
import org.json.JSONObject;
import java.util.List;

public class HomeJsonExample {
    public void run() {
        UnifiedJedis jedis = new UnifiedJedis("redis://localhost:6379");

        JSONObject user1 = new JSONObject()
                .put("name", "Paul John")
                .put("email", "paul.john@example.com")
                .put("age", 42)
                .put("city", "London");
        
        JSONObject user2 = new JSONObject()
                .put("name", "Eden Zamir")
                .put("email", "eden.zamir@example.com")
                .put("age", 29)
                .put("city", "Tel Aviv");
        
        JSONObject user3 = new JSONObject()
                .put("name", "Paul Zamir")
                .put("email", "paul.zamir@example.com")
                .put("age", 35)
                .put("city", "Tel Aviv");

        SchemaField[] schema = {
            TextField.of("$.name").as("name"),
            TextField.of("$.city").as("city"),
            NumericField.of("$.age").as("age")
        };

        String createResult = jedis.ftCreate("idx:users",
            FTCreateParams.createParams()
                .on(IndexDataType.JSON)
                .addPrefix("user:"),
                schema
        );

        System.out.println(createResult); // >>> OK

        String user1Set = jedis.jsonSet("user:1", new Path2("$"), user1);
        String user2Set = jedis.jsonSet("user:2", new Path2("$"), user2);
        String user3Set = jedis.jsonSet("user:3", new Path2("$"), user3);

        SearchResult findPaulResult = jedis.ftSearch("idx:users",
             "Paul @age:[30 40]"
        );
        
        System.out.println(findPaulResult.getTotalResults()); // >>> 1

        List<Document> paulDocs = findPaulResult.getDocuments();

        for (Document doc: paulDocs) {
            System.out.println(doc.getId());
        }
        // >>> user:3

        SearchResult citiesResult = jedis.ftSearch("idx:users",
            "Paul",
            FTSearchParams.searchParams()
                .returnFields("city")
        );

        System.out.println(citiesResult.getTotalResults()); // >>> 2

        for (Document doc: citiesResult.getDocuments()) {
            System.out.println(doc.getId());
        }
        // >>> user:1
        // >>> user:3

        AggregationResult aggResult = jedis.ftAggregate("idx:users",
            new AggregationBuilder("*")
                .groupBy("@city", Reducers.count().as("count"))
        );

        System.out.println(aggResult.getTotalResults()); // >>> 2

        for (Row cityRow: aggResult.getRows()) {
            System.out.println(String.format(
                "%s - %d",
                cityRow.getString("city"), cityRow.getLong("count"))
            );
        }
        // >>> London - 1
        // >>> Tel Aviv - 2

        jedis.close();
    }
}

指定查询选项以仅返回city字段：

Java-Sync

import redis.clients.jedis.UnifiedJedis;
import redis.clients.jedis.exceptions.JedisDataException;
import redis.clients.jedis.json.Path2;
import redis.clients.jedis.search.*;
import redis.clients.jedis.search.aggr.*;
import redis.clients.jedis.search.schemafields.*;
import org.json.JSONObject;
import java.util.List;

public class HomeJsonExample {
    public void run() {
        UnifiedJedis jedis = new UnifiedJedis("redis://localhost:6379");

        JSONObject user1 = new JSONObject()
                .put("name", "Paul John")
                .put("email", "paul.john@example.com")
                .put("age", 42)
                .put("city", "London");
        
        JSONObject user2 = new JSONObject()
                .put("name", "Eden Zamir")
                .put("email", "eden.zamir@example.com")
                .put("age", 29)
                .put("city", "Tel Aviv");
        
        JSONObject user3 = new JSONObject()
                .put("name", "Paul Zamir")
                .put("email", "paul.zamir@example.com")
                .put("age", 35)
                .put("city", "Tel Aviv");

        SchemaField[] schema = {
            TextField.of("$.name").as("name"),
            TextField.of("$.city").as("city"),
            NumericField.of("$.age").as("age")
        };

        String createResult = jedis.ftCreate("idx:users",
            FTCreateParams.createParams()
                .on(IndexDataType.JSON)
                .addPrefix("user:"),
                schema
        );

        System.out.println(createResult); // >>> OK

        String user1Set = jedis.jsonSet("user:1", new Path2("$"), user1);
        String user2Set = jedis.jsonSet("user:2", new Path2("$"), user2);
        String user3Set = jedis.jsonSet("user:3", new Path2("$"), user3);

        SearchResult findPaulResult = jedis.ftSearch("idx:users",
             "Paul @age:[30 40]"
        );
        
        System.out.println(findPaulResult.getTotalResults()); // >>> 1

        List<Document> paulDocs = findPaulResult.getDocuments();

        for (Document doc: paulDocs) {
            System.out.println(doc.getId());
        }
        // >>> user:3

        SearchResult citiesResult = jedis.ftSearch("idx:users",
            "Paul",
            FTSearchParams.searchParams()
                .returnFields("city")
        );

        System.out.println(citiesResult.getTotalResults()); // >>> 2

        for (Document doc: citiesResult.getDocuments()) {
            System.out.println(doc.getId());
        }
        // >>> user:1
        // >>> user:3

        AggregationResult aggResult = jedis.ftAggregate("idx:users",
            new AggregationBuilder("*")
                .groupBy("@city", Reducers.count().as("count"))
        );

        System.out.println(aggResult.getTotalResults()); // >>> 2

        for (Row cityRow: aggResult.getRows()) {
            System.out.println(String.format(
                "%s - %d",
                cityRow.getString("city"), cityRow.getLong("count"))
            );
        }
        // >>> London - 1
        // >>> Tel Aviv - 2

        jedis.close();
    }
}

使用聚合查询来计算每个城市中的所有用户。

Java-Sync

import redis.clients.jedis.UnifiedJedis;
import redis.clients.jedis.exceptions.JedisDataException;
import redis.clients.jedis.json.Path2;
import redis.clients.jedis.search.*;
import redis.clients.jedis.search.aggr.*;
import redis.clients.jedis.search.schemafields.*;
import org.json.JSONObject;
import java.util.List;

public class HomeJsonExample {
    public void run() {
        UnifiedJedis jedis = new UnifiedJedis("redis://localhost:6379");

        JSONObject user1 = new JSONObject()
                .put("name", "Paul John")
                .put("email", "paul.john@example.com")
                .put("age", 42)
                .put("city", "London");
        
        JSONObject user2 = new JSONObject()
                .put("name", "Eden Zamir")
                .put("email", "eden.zamir@example.com")
                .put("age", 29)
                .put("city", "Tel Aviv");
        
        JSONObject user3 = new JSONObject()
                .put("name", "Paul Zamir")
                .put("email", "paul.zamir@example.com")
                .put("age", 35)
                .put("city", "Tel Aviv");

        SchemaField[] schema = {
            TextField.of("$.name").as("name"),
            TextField.of("$.city").as("city"),
            NumericField.of("$.age").as("age")
        };

        String createResult = jedis.ftCreate("idx:users",
            FTCreateParams.createParams()
                .on(IndexDataType.JSON)
                .addPrefix("user:"),
                schema
        );

        System.out.println(createResult); // >>> OK

        String user1Set = jedis.jsonSet("user:1", new Path2("$"), user1);
        String user2Set = jedis.jsonSet("user:2", new Path2("$"), user2);
        String user3Set = jedis.jsonSet("user:3", new Path2("$"), user3);

        SearchResult findPaulResult = jedis.ftSearch("idx:users",
             "Paul @age:[30 40]"
        );
        
        System.out.println(findPaulResult.getTotalResults()); // >>> 1

        List<Document> paulDocs = findPaulResult.getDocuments();

        for (Document doc: paulDocs) {
            System.out.println(doc.getId());
        }
        // >>> user:3

        SearchResult citiesResult = jedis.ftSearch("idx:users",
            "Paul",
            FTSearchParams.searchParams()
                .returnFields("city")
        );

        System.out.println(citiesResult.getTotalResults()); // >>> 2

        for (Document doc: citiesResult.getDocuments()) {
            System.out.println(doc.getId());
        }
        // >>> user:1
        // >>> user:3

        AggregationResult aggResult = jedis.ftAggregate("idx:users",
            new AggregationBuilder("*")
                .groupBy("@city", Reducers.count().as("count"))
        );

        System.out.println(aggResult.getTotalResults()); // >>> 2

        for (Row cityRow: aggResult.getRows()) {
            System.out.println(String.format(
                "%s - %d",
                cityRow.getString("city"), cityRow.getLong("count"))
            );
        }
        // >>> London - 1
        // >>> Tel Aviv - 2

        jedis.close();
    }
}

请参阅Redis查询引擎文档，了解所有查询功能的完整描述及示例。