如何使用 SQLAlchemy 在 PostgreSQL 中创建表？

Question

I tried to create a table in the "app" database, but got this error:

app=# CREATE TABLE users;
ERROR:  syntax error at or near ";"
LINE 1: LINE 1: CREATE TABLE users;
                                  ^

The columns are defined in models.py which is why I don't create them here.

Answer 1

Do not create the tables in PostgreSQL, SQLAlchemy will create the table (and the columns) for you. All you need to do is create the database , which you have done. To create the tables with Flask-SQLAlchemy:

from flask import Flask
from flask_sqlalchemy import SQLAlchemy

app = Flask(__name__)
db = SQLAlchemy(app)

class User(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String, nullable=False, unique=True)

with app.app_context():
    db.create_all()

---

To address the error (although as stated above you should not do this), it is because that is not a full CREATE TABLE expression. You need to specify zero or more columns for the table.

CREATE TABLE my_table ();

Answer 2

In my case forgot to import my Model class and code run without any error:).

If you call create_all() on interactive mode please ensure that you import particular Model class.

Note: Every time you make a change on Model class restart ipython.