flask-sqlalchemy

问题 I'm using Flask and SQLAlchemy (via the Flask-SQLAlchemy extension) together with Factory_Boy. My GearItem model has a foreign key to GearCategory . Factory_Boy handles this through the SubFactory function that creates the object to be used as the foreign key in the original factory. Here are my model definitions: class GearCategory(db.Model): id = db.Column(db.Integer, primary_key=True) name = db.Column(db.Text, unique=True, nullable=False) gear_items = db.relationship('GearItem', backref=

问题 I'm going to be very specific here, because similar questions have been asked, but none of the solutions work for this problem. I'm working on a project that has four postgres databases, but let's say for the sake of simplicity there are 2. Namely, A & B A,B represent two geographical locations, but the tables and schemas in the database are identical. Sample model: from flask_sqlalchemy import SQLAlchemy from sqlalchemy import * from sqlalchemy.ext.declarative import declarative_base db =

问题 My backend configuration is : Ubuntu 12.04 Python 2.7 Flask 0.9 Flask-SQLAlchemy Postgres 9.2 I've got this error message: TimeoutError: QueuePool limit of size 5 overflow 10 reached, connection timed out, timeout 30 Do I need to close explicitly the db.session? Shouldn't be the connection back to pool when session goes out of scope? 回答1: This could happen if you are using debug=True in your application and you have loaded several pages or API endpoints which errored out. The reason is that

问题 SQLAlchemy is undoubtedly very powerful, but the documentation implicitly assumes lots of prior knowledge and on the subject of relationships, mixes between the backref and the newly-preferred back_populates() methods, which I find very confusing. The following model design is pretty much an exact mirror of the guide in the documentation that deals with the Association Objects for many-to-many relationships. You can see that the comments are still identical to those in the original article,

问题 Having following models: class Question(db.Model): id = db.Column(db.Integer(), primary_key=True) title = db.Column(db.String(125)) text = db.Column(db.Text()) answers = db.relationship('Answer', backref='for_question') class Answer(db.Model): id = db.Column(db.Integer(), primary_key=True) text = db.Column(db.Text()) question_id = db.Column(db.Integer(), db.ForeignKey('question.id')) How can I perform select_related in SQLAlchemy/Flask? I've found in documentation that I can make something

问题 how can i define a column as a positive integer using flask sqlalchemy? i am hoping the answer would look something like this: class City(db.Model): id = db.Column(db.Integer, primary_key=True) population = db.Column(db.Integer, positive=True) def __init__(self,population): self.population = population however, this class definition will throw an error b/c sqlalchemy does not know about a 'positive' argument. i could raise an exception if an object is instantiated with a negative value for

问题 I'm a newbie to Flask and SQLAlchemy (been working with Django for the last 3 years). I need to call an existing PostgreSQL function that writes to 3 different tables in a database. This is out of my control (I just have to make it work). The function returns a record (custom Postgres type) with information about the results. Here is the code: from flask.ext.sqlalchemy import SQLAlchemy db = SQLAlchemy() ... retval = db.engine.execute( 'SELECT * FROM add_purchase(%s, %s, %s, %s, %s, %s, %s);'

问题 I'm trying to create one-to-one and one-to-many relationship at the same time in Flask-SQLAlchemy. I want to achieve this: "A group has many members and one administrator." Here is what I did: class Group(db.Model): id = db.Column(db.Integer, primary_key=True) name = db.Column(db.String(140), index=True, unique=True) description = db.Column(db.Text) created_at = db.Column(db.DateTime, server_default=db.func.now()) members = db.relationship('User', backref='group') admin = db.relationship(

问题 class Parent(db.Model): id = db.Column(db.Integer, primary_key = True) name = db.Column(db.String(120)) def __repr_(self): return '<Parent %r>' % (self.name) admin.add_view(ModelView(Parent, db.session)) class Child(db.Model): id = db.Column(db.Integer, primary_key = True) name = db.Column(db.String(120)) parent = db.Column(db.Integer, db.ForeignKey(Parent)) admin.add_view(ModelView(Child, db.session)) Hello - The code above is an example of flask-admin page that I am trying to create. The

问题 I'm trying to get a server for an app working, but I'm getting an error upon login: [!] Object '<User at 0x7f12bc185a90>' is already attached to session '2' (this is '3') It seems the session I'm adding is already on the database. This is the snippet of code that is causing the problem: @app.route('/login', methods=['POST']) def login(): u = User.query.filter(User.username == request.form["username"]).first() if not u or u.password != request.form["password"]: return error("E1") s = Session