A sign-up form creates an account

Runs the sample. Generated for this page; it reads the connection string from the environment.

using ArxSamples.MySQL;
using ArxSamples.MySQL.Operations.Create.RealCases;

// The connection string comes from the environment, never from the code (see "Configure the connection").
var connectionString = Environment.GetEnvironmentVariable("ARX_SAMPLES_MYSQL")
    ?? throw new InvalidOperationException("Set the ARX_SAMPLES_MYSQL environment variable to your MySQL connection string.");

await new RealCase1_SignUpAnAccount().RunAsync(new SampleContext(connectionString));

The sample, as it is in the repository.

using ARX.SDK.Models;
using ARX.SDK.Services;
using static ArxSamples.MySQL.SampleOutput;

namespace ArxSamples.MySQL.Operations.Create.RealCases;

/// <summary>
/// A sign-up form creates a customer account, in three scenarios: the account from the form (columns left out get their
/// database defaults), a subsidiary that points at its parent, and form fields the table doesn't have (ArxIgnore).
/// </summary>
public sealed class RealCase1_SignUpAnAccount : ISample
{
    public string Name => "create-real-1-sign-up-an-account";

    public string Title => "A sign-up form creates an account";

    public async Task RunAsync(SampleContext dbContext)
    {
        var account = await Scenario1_CreateTheAccountFromTheFormAsync(dbContext);

        await Scenario2_ASubsidiaryPointsAtItsParentAsync(dbContext, account);

        await Scenario3_FormFieldsTheTableDoesNotHaveAsync(dbContext);
    }

    /// <summary>1. The account from the sign-up form. guid, status and created_on aren't set: the database fills them in.</summary>
    private static async Task<ArxEntity> Scenario1_CreateTheAccountFromTheFormAsync(SampleContext dbContext)
    {
        Step("1. Create the account from the form");

        var account = new ArxEntity("account");
        account["name"] = "Northwind Traders";
        account["account_number"] = "ACC-10001";
        account["industry"] = new ArxSelectionSetValue("Industry", Industry.Retail);
        account["website"] = "https://northwind.example";
        account["annual_revenue"] = 12_500_000.00m;
        account["employee_count"] = 240;
        account["is_key_account"] = true;
        account["founded_on"] = new DateOnly(1998, 4, 1);
        account["modified_on"] = DateTime.UtcNow;

        var id = await dbContext.Service.CreateAsync(account);
        Show($"account {id} (also on account.RecordId)");

        // guid, status and created_on weren't set: MySQL filled in their defaults.
        var stored = await dbContext.Direct.RowAsync("account", id.AsInt64());
        Show($"defaults: guid {stored["guid"]}, status {stored["status"]}, created_on {stored["created_on"]:u}");

        /* ===========================================================
         * [DIRECT QUERY CHECK]
         * -----------------------------------------------------------
         * SELECT id, name, account_number, industry, website, annual_revenue, guid, status, created_on
         * FROM account
         * WHERE account_number = 'ACC-10001';
         * -- Expect: 1 row; guid, status and created_on are the database defaults.
         * ===========================================================
         */

        return account;
    }

    /// <summary>2. A subsidiary account points at its parent with a lookup.</summary>
    private static async Task Scenario2_ASubsidiaryPointsAtItsParentAsync(SampleContext dbContext, ArxEntity parent)
    {
        Step("2. Add a subsidiary that points at its parent");

        var subsidiary = new ArxEntity("account");
        subsidiary["name"] = "Northwind Traders (Canada)";
        subsidiary["account_number"] = "ACC-10002";
        subsidiary["parent_account_id"] = new ArxEntityReference("account", parent.RecordId);

        var id = await dbContext.Service.CreateAsync(subsidiary);
        Show($"subsidiary {id}, parent_account_id {(await dbContext.Direct.RowAsync("account", id.AsInt64()))["parent_account_id"]}");

        /* ===========================================================
         * [DIRECT QUERY CHECK]
         * -----------------------------------------------------------
         * SELECT s.name, s.account_number, s.parent_account_id, p.name AS parent
         * FROM account s
         * JOIN account p ON p.id = s.parent_account_id
         * WHERE s.account_number = 'ACC-10002';
         * -- Expect: 1 row, Northwind Traders (Canada), parent Northwind Traders.
         * ===========================================================
         */
    }

    /// <summary>3. A form field the table doesn't have stays on the entity, marked ArxIgnore, and isn't written.</summary>
    private static async Task Scenario3_FormFieldsTheTableDoesNotHaveAsync(SampleContext dbContext)
    {
        Step("3. Form fields the table doesn't have are marked ArxIgnore");

        var fromForm = new ArxEntity("account");
        fromForm["name"] = "Contoso Pharmaceuticals";
        fromForm["industry"] = new ArxSelectionSetValue("Industry", Industry.Healthcare);
        fromForm["display_label"] = new ArxIgnore();

        // The id column "id" is declared Generated, and the form doesn't set it, so the database fills it in. An id you do
        // set is written as given, so leave the id attribute out unless you mean it.
        var id = await dbContext.Service.CreateAsync(fromForm);
        Show($"account {id}: display_label wasn't sent, and the database chose the id");

        /* ===========================================================
         * [DIRECT QUERY CHECK]
         * -----------------------------------------------------------
         * SELECT id, name, industry
         * FROM account
         * WHERE name = 'Contoso Pharmaceuticals' AND account_number IS NULL;
         * -- Expect: 1 row, industry 3 (Healthcare); there is no display_label column.
         * ===========================================================
         */
    }
}

  > 1. Create the account from the form
      account 1 (also on account.RecordId)
      defaults: guid daea56e4-de48-11f1-8688-429545a106a5, status ACTIVE, created_on 2026-11-12 03:26:31Z
  > 2. Add a subsidiary that points at its parent
      subsidiary 2, parent_account_id 1
  > 3. Form fields the table doesn't have are marked ArxIgnore
      account 3: display_label wasn't sent, and the database chose the id