Databases
Databases gives you simple asyncio support for a range of databases.
It allows you to make queries using the powerful SQLAlchemy Coreexpression language, and provides support for PostgreSQL, MySQL, and SQLite.
Databases is suitable for integrating against any async Web framework, such as Starlette,Sanic, Responder, Quart, aiohttp, Tornado, or FastAPI.
Documentation: https://www.encode.io/databases/
Requirements: Python 3.6+
Installation
$ pip install databases
You can install the required database drivers with:
$ pip install databases[postgresql]
$ pip install databases[mysql]
$ pip install databases[sqlite]
Driver support is provided using one of asyncpg, aiomysql, or aiosqlite.Note that if you are using any synchronous SQLAlchemy functions such as engine.create_all() or alembic migrations then you still have to install a synchronous DB driver: psycopg2 for PostgreSQL and pymysql for MySQL.
Quickstart
For this example we'll create a very simple SQLite database to run somequeries against.
$ pip install databases[sqlite]
$ pip install ipython
We can now run a simple example from the console.
Note that we want to use ipython here, because it supports using awaitexpressions directly from the console.
# Create a database instance, and connect to it.
from databases import Database
database = Database('sqlite:///example.db')
await database.connect()
# Create a table.
query = """CREATE TABLE HighScores (id INTEGER PRIMARY KEY, name VARCHAR(100), score INTEGER)"""
await database.execute(query=query)
# Insert some data.
query = "INSERT INTO HighScores(name, score) VALUES (:name, :score)"
values = [
{"name": "Daisy", "score": 92},
{"name": "Neil", "score": 87},
{"name": "Carol", "score": 43},
]
await database.execute_many(query=query, values=values)
# Run a database query.
query = "SELECT * FROM HighScores"
rows = await database.fetch_all(query=query)
print('High Scores:', rows)
Check out the documentation on making database queriesfor examples of how to start using databases together with SQLAlchemy core expressions.
—
Databases is BSD licensed code. Designed & built in Brighton, England.
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