UQL Execution

This section introduces the Uql() and UqlStream() methods on a Connection object for querying the database using UQL.

Each example focuses solely on the method's usage. For a complete code example, please refer to the full example.

NOTE

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

Uql()

Executes a UQL query on the current graphset or the database and returns the result.

Parameters:

• string: The UQL query to be executed.
• RequestConfig (Optional): Configuration settings for the request.

Returns:

• Response: Result of the request.

C#
// Retrieves 5 @movie nodes in graphset 'miniCircle' and prints their name

RequestConfig requestConfig = new RequestConfig() { Graph = "miniCircle", UseMaster = true };

var res = await ultipa.Uql("find().nodes({@movie}) as n return n{*} limit 5", requestConfig);
var nodeList = res?.Alias("n")?.AsNodes();
foreach (var node in nodeList)
{
    Console.WriteLine(node.Values.GetValueOrDefault("name"));
}

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

For more examples, please refer to Types Mapping Ultipa and C#.

UqlStream()

Executes a UQL query on the current graphset or the database and returns the result incrementally, allowing handling of large datasets without loading everything into memory at once.

Parameters:

• string: The UQL query to be executed.
• UqlResponseStream: Listener for the streaming process.
• RequestConfig (Optional): Configuration settings for the request.

Returns:

• void

C#
// Retrieves all 1-step paths in graphset 'miniCircle'
RequestConfig requestConfig = new RequestConfig() { Graph = "miniCircle", UseMaster = true };

var count = 0;
await ultipa.UqlStream(
    "n().e().n() as paths return paths{*}",
    new UqlResponseStream()
    {
        OnStart = () => Console.WriteLine("Start"),
        OnData = (
            resp =>
            {
                if (resp.Status.ErrorCode != ErrorCode.Success)
                {
                    Console.WriteLine(resp.Status.Msg);
                }
                var paths = resp.Get(0)?.AsPaths();

                Console.WriteLine($"Count ={paths.Count()}");
                return true;
            }
        ),

        OnEnd = () => Console.WriteLine("End"),
    },
    requestConfig
);

Output
Start
Count =  1390
End

Full Example

C#
using System.Security.Cryptography.X509Certificates;
using Microsoft.Extensions.Logging;
using Newtonsoft.Json;
using UltipaService;
using UltipaSharp;
using UltipaSharp.api;
using UltipaSharp.configuration;
using UltipaSharp.connection;
using UltipaSharp.exceptions;
using UltipaSharp.structs;
using UltipaSharp.utils;
using Logger = UltipaSharp.utils.Logger;
using Property = UltipaSharp.structs.Property;
using Schema = UltipaSharp.structs.Schema;

class Program
{
    static async Task Main(string[] args)
    {
        // Connection configurations
        //URI example: Hosts=new[]{"mqj4zouys.us-east-1.cloud.ultipa.com:60010"}
        var myconfig = new UltipaConfig()
        {
            Hosts = new[] { "192.168.1.85:60061", "192.168.1.86:60061", "192.168.1.87:60061" },
            Username = "***",
            Password = "***",
        };

        // Establishes connection to the database
        var ultipa = new Ultipa(myconfig);
        var isSuccess = ultipa.Test();
        Console.WriteLine(isSuccess);


        // Request configurations
        RequestConfig requestConfig = new RequestConfig() { Graph = "miniCircle", UseMaster = true };

        // Retrieves 10 nodes and prints the _id and name property value of the first returned one
        var res = await ultipa.Uql(
            "find().nodes({@movie}) as n return n{*} limit 10",
            requestConfig
        );

        var nodeList = res?.Get(0).AsNodes();
        if (nodeList[0].Values.TryGetValue("name", out object? value))
        {
            Console.WriteLine(value);
        }
        Console.WriteLine(nodeList[0].Id);
    }
}