I am new to SQLAlchemy and aiopg. After defined a Tabled object and finished DB initialization, I wanted to fetch one row with specified id in aiohttp server.
import aiopg.sa
from sqlalchemy import (
MetaData, Table, Column, ForeignKey,
Integer, String, Date
)
...
product = Table(
'product', meta,
Column('id', Integer, primary_key=True),
Column('Name', String(200), nullable=False),
Column('Description', String(200), nullable=False),
Column('Price', Integer, nullable=False),
)
async def init_pg(app):
conf = app['config']['postgres']
engine = await aiopg.sa.create_engine(
database=conf['database'],
user=conf['user'],
password=conf['password'],
host=conf['host'],
port=conf['port'],
minsize=conf['minsize'],
maxsize=conf['maxsize'],
)
app['db'] = engine
After spending all afternoon, finally I figured it out. text can convert string as TextClause and it can be used in Whereclause.
https://docs.sqlalchemy.org/en/13/core/selectable.html#sqlalchemy.sql.expression.select
from sqlalchemy import text
...
async with request.app['db'].acquire() as conn:
whereclause = text('id = {}'.format(request.match_info['id']))
cursor = await conn.execute(db.product.select(whereclause=whereclause))
record = await cursor.fetchone()
product = Product(*record.values())
I am really happy to know it :) and I had better look into Official Document more carefully.
Top comments (0)