Dialects¶

Install only the driver needed by the application.

PostgreSQL¶

import asyncpg

from pysely import PostgresDialect, Pysely


pool = await asyncpg.create_pool("postgresql://user:password@localhost/app")
db = Pysely[object](dialect=PostgresDialect(pool=pool))

Install with uv sync --extra postgres. Pysely acquires connections from the provided pool and closes the pool when db.destroy() runs.

MySQL¶

import asyncmy

from pysely import MysqlDialect, Pysely


pool = await asyncmy.create_pool(
    host="127.0.0.1",
    user="app",
    password="secret",
    db="app",
    autocommit=True,
)
db = Pysely[object](dialect=MysqlDialect(pool=pool))

Install with uv sync --extra mysql. MySQL pools must have autocommit enabled. Pysely closes the pool when db.destroy() runs.

SQLite¶

import aiosqlite

from pysely import Pysely, SqliteDialect


database = await aiosqlite.connect("app.db", isolation_level=None)
db = Pysely[object](dialect=SqliteDialect(database=database))

Install with uv sync --extra sqlite. SQLite databases must use autocommit. Use async with or call await db.destroy() to close the database.

Each dialect also accepts an async factory for lazy initialization:

async def create_pool():
    return await asyncpg.create_pool("postgresql://localhost/app")


db = Pysely[object](dialect=PostgresDialect(pool=create_pool))