UQL Execution

This section introduces the uql() and uqlStream() methods to execute UQL in the database.

NOTE

UQL (Ultipa Query Language) is the native language designed by Ultipa to fully interact with Ultipa graph databases. For detailed information on UQL, refer to the documentation.

uql()

Executes an UQL query in the database.

Parameters

• uql: String: The UQL query to be executed.
• config: RequestConfig (Optional): Request configuration.

Returns

• Response: Response of the request.

Java
// Retrieves 5 movie nodes from the graph 'miniCircle'

RequestConfig requestConfig = new RequestConfig();
requestConfig.setGraph("miniCircle");

Response response = driver.uql("find().nodes({@movie}) as n return n{*} limit 5", requestConfig);
List<Node> nodeList = response.alias("n").asNodes();
for (Node node : nodeList) {
    System.out.println(node.get("name"));
}

Output
The Shawshank Redemption
Farewell My Concubine
Léon: The Professional
Titanic
Life is Beautiful

uqlStream()

Executes an UQL query in the database and returns the results incrementally, allowing handling of large datasets without loading everything into memory at once.

Parameters

• uql: String: The UQL query to be executed.
• cb: QueryResponseListener: Listener for the streaming process.
• config: RequestConfig (Optional): Request configuration.

Returns

• None

Java
// Retrieves all 1-step paths from the graph 'miniCircle'

RequestConfig requestConfig = new RequestConfig();
requestConfig.setGraph("miniCircle");

driver.uqlStream("n().e().n() as paths return paths{*}", new QueryResponseListener() {
    int count = 0;

    public void onReady() {
    	System.out.println("Start downloading");
    }

    public void next(Response response) {
    	if (response.getStatus().getCode() != Ultipa.ErrorCode.SUCCESS){
      	System.out.println(response.getStatus().getMsg());
      }
      List<Path> paths = response.get(0).asPaths();
      count += paths.size();
      System.out.println("count = " + count);
    }

    public void onComplete() {
    	System.out.println("Done");
    	System.out.println("count = " + count);
    }

    public void onError(Throwable throwable) {
    	System.out.println("Error");
    }
}, requestConfig);

Output
count = 1024
count = 2048
count = 3072
count = 3220
count = 3621
count = 3849
Done
count = 3849

Full Example

Main.java
package com.ultipa.www.sdk.api;

import com.ultipa.sdk.UltipaDriver;
import com.ultipa.sdk.connect.conf.RequestConfig;
import com.ultipa.sdk.connect.conf.UltipaConfig;
import com.ultipa.sdk.operate.entity.Node;
import com.ultipa.sdk.operate.response.Response;
import org.assertj.core.util.Lists;

import java.util.List;

public class Main {
    public static void main(String[] args) {
        UltipaConfig ultipaConfig = UltipaConfig.config()
                // URI example: .hosts(Lists.newArrayList("d3026ac361964633986849ec43b84877s.eu-south-1.cloud.ultipa.com:8443"))
                .hosts(Lists.newArrayList("192.168.1.85:60061","192.168.1.88:60061","192.168.1.87:60061"))
                .username("<username>")
                .password("<password>");

        UltipaDriver driver = null;

        try {
            driver = new UltipaDriver(ultipaConfig);

            // Retrieves 5 movie nodes from the graph 'miniCircle'

            RequestConfig requestConfig = new RequestConfig();
            requestConfig.setGraph("miniCircle");

            Response response = driver.uql("find().nodes({@movie}) as n return n{*} limit 5", requestConfig);
            List<Node> nodeList = response.alias("n").asNodes();
            for (Node node : nodeList) {
                System.out.println(node.get("name"));
            }
        } catch (InterruptedException e) {
            throw new RuntimeException(e);
        } finally {
            if (driver != null) {
                driver.close();
            }
        }
    }
}