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

     * </ul>
     * @throws DuplicateProjectException if any projects are duplicated by id
     */
    // MAVENAPI FIXME: the DAG used is NOT only used to represent the dependency relation,
    // but also for <parent>, <build><plugin>, <reports>. We need multiple DAG's
    // since a DAG can only handle 1 type of relationship properly.
    // Use case:  This is detected as a cycle:

Así que usamos un import relativo con `..` para las dependencias:

{* ../../docs_src/bigger_applications/app_an_py39/routers/items.py hl[3] title["app/routers/items.py"] *}

#### Cómo funcionan los imports relativos { #how-relative-imports-work }

/// tip | Consejo

Si sabes perfectamente cómo funcionan los imports, continúa a la siguiente sección.

///

Un solo punto `.`, como en:

```Python

Então usamos uma importação relativa com `..` para as dependências:

{* ../../docs_src/bigger_applications/app_an_py39/routers/items.py hl[3] title["app/routers/items.py"] *}

#### Como funcionam as importações relativas { #how-relative-imports-work }

/// tip | Dica

Se você sabe perfeitamente como funcionam as importações, continue para a próxima seção abaixo.

///

Um único ponto `.`, como em:

```Python

            final SearchHits searchHits = searchResponse.getHits();
            builder.allRecordCount(searchHits.getTotalHits().value());
            builder.allRecordCountRelation(searchHits.getTotalHits().relation().toString());
            builder.queryTime(searchResponse.getTook().millis());

            if (searchResponse.getTotalShards() != searchResponse.getSuccessfulShards()) {
                builder.partialResults(true);

func NewDummyDataGen(totalLength, skipOffset int64) io.ReadSeeker {
	if totalLength < 0 {
		panic("Negative length passed to DummyDataGen!")
	}
	if skipOffset < 0 {
		panic("Negative rotations are not allowed")
	}

	skipOffset %= int64(len(alphabets))
	const multiply = 100
	as := bytes.Repeat(alphabets, multiply)
	b := as[skipOffset : skipOffset+int64(len(alphabets)*(multiply-1))]
	return &DummyDataGen{

Commercial Contributor in connection with its distribution of the Program
in a commercial product offering. The obligations in this section do not
apply to any claims or Losses relating to any actual or alleged
intellectual property infringement. In order to qualify, an Indemnified
Contributor must: a) promptly notify the Commercial Contributor in

# Bancos de Dados SQL (Relacionais) { #sql-relational-databases }

**FastAPI** não exige que você use um banco de dados SQL (relacional). Mas você pode usar **qualquer banco de dados** que quiser.

Aqui veremos um exemplo usando <a href="https://sqlmodel.tiangolo.com/" class="external-link" target="_blank">SQLModel</a>.

to the extent caused by the acts or omissions of such Commercial Contributor
in connection with its distribution of the Program in a commercial product
offering. The obligations in this section do not apply to any claims or Losses
relating to any actual or alleged intellectual property infringement. In order
to qualify, an Indemnified Contributor must: a) promptly notify the Commercial
Contributor in writing of such claim, and b) allow the Commercial Contributor

También, el mejor enfoque era usar estándares ya existentes.

Entonces, antes de siquiera empezar a programar **FastAPI**, pasé varios meses estudiando las especificaciones de OpenAPI, JSON Schema, OAuth2, etc. Entendiendo su relación, superposición y diferencias.

## Diseño { #design }

Luego pasé algún tiempo diseñando la "API" de desarrollador que quería tener como usuario (como desarrollador usando FastAPI).