.NET | SDK | Data Types

Data Types

The .NET SDK translates datatypes native to SurrealQL into either datatypes native to .NET, or a custom implementation. This document describes all datatypes, and links to their respective documentation.

Data Types overview

Datatype	Kind	Documentation
String	Native	`String`
Number	Native	Any number type, e.g. `Int32`,`Single`
Float	Native	Any number type, e.g. `Int32`,`Single`
Bool	Native	`Boolean`
Null	Native	`null`
None	Custom	`None`
Array	Native	Any `IEnumerable` representation
Object	Native	Any `Object` representation
Datetime	Native	`DateTime`or`DateOnly`
Binary	Native	`byte[]`
Uuid	Native	`Guid`
Duration	Native	`TimeSpan`or`TimeOnly`
Decimal	Native	`Decimal`
Geometry	via Microsoft.Spatial	`Geometry` or `Geography` representations
Table	Native	`String`
RecordId	Custom	`RecordId`

`None`

The None type is a custom type that represents the absence of a value.

Signature
public readonly struct None { }

Working with `None`

Constructing
var none = new None();

// Change the value of a record to None
var myRecord = new MyRecord();
myRecord.Value = new None();

`RecordId`

When you receive a RecordId back from SurrealDB, it will always be represented as a RecordId. The class holds Table and Id fields, representing the table name, and a unique identifier for the record on that table.

Signature
public class RecordId
{
    public string Table { get; }

    public T DeserializeId<T>();

    // ... The rest is omitted for brevity
}

The RecordId is a non-generic class, allowing you to extract the Id field by providing the output type via the DeserializeId method. This can helpful when the RecordId is used in a generic context, for when you store the Id as an Object or an Array for example.

For cases where you are aware of the type of the Id field, you can use the generic version of RecordId to avoid the need for manual deserialization.

Signature with generics
public class RecordIdOf<T> : RecordId
{
    public T Id { get; }
}

The default type of an Id in SurrealDB being a string, you can choose to use the default provided type RecordIdOfString.

Default RecordId
public class RecordIdOfString : RecordIdOf<string>
{
    // The available properties, inherited from `RecordId` and `RecordIdOf<string>`
    public string Table { get; }
    public string Id { get; }
}

Working with `RecordId`

The simplest and most common way to construct a RecordId is with a tuple (table, id).

Constructing
// Table is "person"
// Unique identifier on the table is "john"
RecordId personId = ("person", "john");
// or
var personId = (RecordId)("person", "john");

This tuple is implicitly converted into a RecordId object. You can use it with all SDK methods:

Using RecordId
await db.Select<Person>(("person", "john"));
await db.Delete(("person", "john"));

You are not exclusively limited to the string type for the Id part. Several overloads exist for different id types:

Constructing
RecordId rid1 = ("person", "alice");           // string
RecordId rid2 = ("person", 123);               // int
RecordId rid3 = ("person", 123L);              // long
RecordId rid4 = ("person", (short)5);          // short
RecordId rid5 = ("person", (byte)7);           // byte
RecordId rid6 = ("person", Guid.NewGuid());    // Guid

Extracting data

The .NET SDK handles serialization and deserialization of the Table and Id parts in Record Id. The serialization is done automatically when sending data to the server. However, deserialization may need to be done manually according to the data type of the Id field. Below are some examples:

Simple record id
RecordId rid = ("person", "john");
string table = rid.Table; // "person"
string id = rid.DeserializeId<string>(); // "john"

Record id with simple data type (other than string)
RecordId rid = ("table", 42);
string table = rid.Table; // "table"
int id = rid.DeserializeId<int>(); // 42

Record id with complex data types
var rid = new RecordIdOf<CityId>("table", new CityId { City = "London" });
var id = rid.DeserializeId<CityId>(); // CityId { City = "London" }

var rid = new RecordIdOf<(string, int)>("table", ("London", 42));
var id = rid.DeserializeId<(string, int)>(); // ("London", 42)

Send back string

If you need to send back a Record Id in string format, you can do so with the StringRecordId class.

We do not implement the parsing of Record Ids in the .NET SDK, as that would mean that we need to be able to parse any SurrealQL value, which comes with a cost. Instead you can send it over as a string with StringRecordId, allowing the server to handle the parsing.

Signature
public class StringRecordId
{
    public string Value { get; }
}

Working with a `StringRecordId`

Constructing
// Table is "person"
// Unique identifier on the table is "john"
var rid = new StringRecordId("person:john");

// Alternatively, a StringRecordId can be inferred explicitly from a string
var rid = (StringRecordId)"person:john";
await client.Select<Person>((StringRecordId)"person:john");

Working with `RecordIdOfString`

For string-based identifiers, you can also use the specialized type RecordIdOfString:

Using RecordIdOfString
var rid = new RecordIdOfString("person", "john");
// or
Console.WriteLine(rid.Table); // "person"
Console.WriteLine(rid.Id);    // "john"

Working with `RecordIdOf<T>`

For complex or structured identifiers, use the generic type RecordIdOf<T>:

Using RecordIdOf<T>
public class CityId
{
    public string City { get; set; } = string.Empty;
}

var rid = new RecordIdOf<CityId>("city", new CityId { City = "London" });

This enables strongly-typed IDs that map directly to your domain objects.

Inheriting from Record

If your model class inherits from Record, it will automatically include an Id property of type RecordId.

Inheriting from Record
public class Person : Record
{
    public string Name { get; set; } = string.Empty;
}

// Example usage
var person = new Person { Name = "Alice" };
Console.WriteLine(person.Id); // RecordId ("person", "…")

Using Data Annotations

The SDK supports attributes for serialization and deserialization.

CBOR serialization

Use CborProperty to map C# properties to SurrealDB fields:

Using CborProperty
[CborProperty("first_name")]
public string FirstName { get; set; } = string.Empty;

RecordIdJsonConverter

Use RecordIdJsonConverter to indicate that a property should be serialized as a RecordId reference to another table:

Using RecordIdJsonConverter
[RecordIdJsonConverter("payment_details")]
public RecordId? PaymentDetails { get; set; }

[RecordIdJsonConverter("payment_details")]
public RecordId? PaymentDetails { get; set; }

Combining attributes

You can combine both attributes on the same property:

Combining attributes
[CborProperty("payment_details")]
[RecordIdJsonConverter("payment_details")]
public RecordId? PaymentDetails { get; set; }

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