無法在Flask應用程序中創建sqlite3數據庫？

Question

我有以下腳本：

#!flask/bin/python
import os

from flask import Flask, render_template, request, url_for
from flask.ext.sqlalchemy import SQLAlchemy

app = Flask("hello")

basedir = os.path.abspath(os.path.dirname(__file__))
SQLALCHEMY_DATABASE_URI = 'sqlite:///' + os.path.join(basedir, 'app.sqlite3')
print SQLALCHEMY_DATABASE_URI
db = SQLAlchemy(app)

db.create_all()

print db

但是當我實際運行腳本時，什么也沒看到：

$ python db_create.py
sqlite:////home/ubuntu/Paw/paw/app.sqlite3
/home/ubuntu/.virtualenvs/paw-py/local/lib/python2.7/site-packages/flask_sqlalchemy/__init__.py:800: UserWarning: SQLALCHEMY_TRACK_MODIFICATIONS adds significant overhead and will be disabled by default in the future.  Set it to True to suppress this warning.
  warnings.warn('SQLALCHEMY_TRACK_MODIFICATIONS adds significant overhead and will be disabled by default in the future.  Set it to True to suppress this warning.')
<SQLAlchemy engine='sqlite://'>

那么，為什么我看到SQLAlchemy引擎被放置在內存中？

我的權限似乎也沒有錯。

Answer 1

您所要做的就是創建一個名為SQLALCHEMY_DATABASE_URI的變量。 您沒有做任何事情告訴SQLAlchemy使用該值。

如文檔所示，您需要將其傳遞給app.config ：

app = Flask(__name__)
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///' + os.path.join(basedir, 'app.sqlite3')
db = SQLAlchemy(app)