# SQL (Relational) Databases { #sql-relational-databases }

**FastAPI** doesn't require you to use a SQL (relational) database. But you can use **any database** that you want.

Here we'll see an example using <a href="https://sqlmodel.tiangolo.com/" class="external-link" target="_blank">SQLModel</a>.

# Testing a Database { #testing-a-database }

You can study about databases, SQL, and SQLModel in the <a href="https://sqlmodel.tiangolo.com/" class="external-link" target="_blank">SQLModel docs</a>. 🤓

There's a mini <a href="https://sqlmodel.tiangolo.com/tutorial/fastapi/" class="external-link" target="_blank">tutorial on using SQLModel with FastAPI</a>. ✨

This also means that in many cases you can pass the same object you get from a request **directly to the database**, as everything is validated automatically.

The same applies the other way around, in many cases you can just pass the object you get from the database **directly to the client**.

You will see examples of this in the next chapters, about relational and NoSQL databases, security, etc.

## **FastAPI** compatibility { #fastapi-compatibility }

The simplicity of the dependency injection system makes **FastAPI** compatible with:

* all the relational databases
* NoSQL databases
* external packages
* external APIs
* authentication and authorization systems

## Other data types { #other-data-types }

Here are some of the additional data types you can use:

* `UUID`:
    * A standard "Universally Unique Identifier", common as an ID in many databases and systems.
    * In requests and responses will be represented as a `str`.
* `datetime.datetime`:
    * A Python `datetime.datetime`.

 * This form extends CreateForm to include fields necessary for updating existing data config entries,
 * including tracking information for optimistic locking and audit trails.
 * Data configs define how to crawl and extract data from databases, CSV files, and other data sources.
 *
 */
public class EditForm extends CreateForm {

    /**
     * Creates a new EditForm instance.
     */
    public EditForm() {
        super();
    }

import jakarta.validation.constraints.Size;

/**
 * Form class for creating data store configurations.
 * Data configs allow administrators to set up crawling of various data sources
 * including databases, CSV files, and other structured data sources.
 */
public class CreateForm {

    /**
     * Creates a new CreateForm instance.
     */
    public CreateForm() {
        // Default constructor
    }

                + "The job with identifier XYZ123 was expected to be in the system but could not be located "
                + "after searching through all available job registries and scheduled task databases.";

        JobNotFoundException exception = new JobNotFoundException(message);

        assertNotNull(exception);
        assertEquals(message, exception.getMessage());
        assertNull(exception.getCause());

notify_nats           publish bucket notifications to NATS endpoints
notify_nsq            publish bucket notifications to NSQ endpoints
notify_mysql          publish bucket notifications to MySQL databases
notify_postgres       publish bucket notifications to Postgres databases
notify_elasticsearch  publish bucket notifications to Elasticsearch endpoints
notify_redis          publish bucket notifications to Redis datastores
```

 *
 * <p>Data configurations define how the crawler should access and process
 * various data sources such as databases, CSV files, or other structured data.</p>
 */
public class DataConfigService extends FessAppService {

    /**
     * DBFlute behavior for data configuration operations.
     * Provides database access methods for DataConfig entities.
     */
    @Resource
    protected DataConfigBhv dataConfigBhv;

    /**