# 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**.

# Test Guide

```bash
cd tests
# prepare test databases
docker-compose up

# run all tests
./tests_all.sh

    page = context.new_page()
    page.goto("http://localhost:8000/docs")
    page.get_by_label("post /heroes/").click()
    # Manually add the screenshot
    page.screenshot(path="docs/en/docs/img/tutorial/sql-databases/image02.png")

    # ---------------------
    context.close()
    browser.close()


process = subprocess.Popen(
    ["fastapi", "run", "docs_src/sql_databases/tutorial002.py"],
)
try:

    page = context.new_page()
    page.goto("http://localhost:8000/docs")
    page.get_by_label("post /heroes/").click()
    # Manually add the screenshot
    page.screenshot(path="docs/en/docs/img/tutorial/sql-databases/image01.png")

    # ---------------------
    context.close()
    browser.close()


process = subprocess.Popen(
    ["fastapi", "run", "docs_src/sql_databases/tutorial001.py"],
)
try:

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

## **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
* API usage monitoring systems

* SQL Builder, Upsert, Locking, Optimizer/Index/Comment Hints, NamedArg, Search/Update/Create with SQL Expr
* Composite Primary Key
* Auto Migrations
* Logger
* Extendable, flexible plugin API: Database Resolver (Multiple Databases, Read/Write Splitting) / Prometheus…
* Every feature comes with tests
* Developer Friendly

## Getting Started

* GORM Guides [https://gorm.io](https://gorm.io)

		Claims: map[string]interface{}{
			"groups": []string{"data-science"},
		},
	},
	"bbb": {
		User:               "Bart",
		MaxValiditySeconds: 3600,
		Claims: map[string]interface{}{
			"groups": []string{"databases"},
		},
	},
}

func mainHandler(w http.ResponseWriter, r *http.Request) {
	token := r.FormValue("token")
	if token == "" {
		writeErrorResponse(w, errors.New("token parameter not given"))
		return
	}

* Automatic annotation and documentation.

## 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`.

Here's a little bit of that history.

## Alternatives

I have been creating APIs with complex requirements for several years (Machine Learning, distributed systems, asynchronous jobs, NoSQL databases, etc), leading several teams of developers.

As part of that, I needed to investigate, test and use many alternatives.

The history of **FastAPI** is in great part the history of its predecessors.