flask-sqlalchemy

问题 I'm using Flask and SQLAlchemy. I have used my own abstract base class and inheritance. When I try to use my models in the python shell I get the following error: >>> from schedule.models import Task Traceback (most recent call last): File "<console>", line 1, in <module> File "/home/teelf/projects/schedule/server/schedule/models.py", line 14, in <module> class User(Base): File "/home/teelf/projects/schedule/server/venv/lib/python3.4/site-packages/flask_sqlalchemy/__init__.py", line 536, in _

问题 So I am using Amazon Web Services RDS to run a MySQL server and using Python's Flask framework to run the application server and Flask-SQLAlchemy to interface with the RDS. My app config.py SQLALCHEMY_DATABASE_URI = '<RDS Host>' SQLALCHEMY_POOL_RECYCLE = 60 My __ init __.py from flask import Flask from flask.ext.sqlalchemy import SQLAlchemy application = Flask(__name__) application.config.from_object('config') db = SQLAlchemy(application) I have my main application.py from flask import Flask

问题 I'm using Flask, Flask-SQLAlchemy, Flask-Marshmallow + marshmallow-sqlalchemy, trying to implement REST api PUT method. I haven't found any tutorial using SQLA and Marshmallow implementing update. Here is the code: class NodeSchema(ma.Schema): # ... class NodeAPI(MethodView): decorators = [login_required, ] model = Node def get_queryset(self): if g.user.is_admin: return self.model.query return self.model.query.filter(self.model.owner == g.user) def put(self, node_id): json_data = request.get

问题 I want to define a specific schema for a 'model' using flask-sqlalchemy. When you create a table object in sqlalchemy itself it has a parameter to pass for schema name. How do I do this in flask-sqlalchemy? 回答1: When you define your model class use: __table_args__ = {"schema":"schema_name"} maybe it will save someone else some hunting. 回答2: For future references: db = flask.ext.sqlalchemy.SQLAlchemy(app) app.config['SQLALCHEMY_DATABASE_URI'] = 'your_default_schema_db_uri' app.config[

问题 I am developing an app which obtains financial data from the Federal Reserve, stores it in a SQlite database using Flask-SQlalchemy, and then serves the data to my front-end dashboard (Bokeh). The data I am using is structured as follows: date realtime_end realtime_start value 0 1962-01-02 2018-08-02 2018-08-02 4.06 1 1962-01-03 2018-08-02 2018-08-02 4.03 2 1962-01-04 2018-08-02 2018-08-02 3.99 3 1962-01-05 2018-08-02 2018-08-02 4.02 4 1962-01-08 2018-08-02 2018-08-02 4.03 5 1962-01-09 2018

问题 If I have a User and Item model, and they have a many-to-many association with each other, how do I build a query that returns: (1) All items that belong to any user named 'Bob' I tried: Item.query.filter(User.name == 'Bob') Which returns all items regardless of the user's name (incorrect) (2) All items that have the name 'shark' and belong to any user named 'Bob' I tried: Item.query.filter(User.name == 'Bob' & Item.name == 'shark') Same as above, but only returns items named 'shark'

问题 There is a student whose type attribute is 4 and the minimum value for type attribute can be 1. In postgres In session 1, I exclusively lock and update a row in the student table: BEGIN; LOCK TABLE students IN ROW EXCLUSIVE MODE; SELECT * FROM students WHERE id = 122 FOR UPDATE; UPDATE students SET type = 1 WHERE id = 122; END; In session 2 I concurrently run: UPDATE students SET type = type - 1 WHERE id = 122; The result I get is an exception, i.e student's type can't be lower than 1 in

问题 There is a student whose type attribute is 4 and the minimum value for type attribute can be 1. In postgres In session 1, I exclusively lock and update a row in the student table: BEGIN; LOCK TABLE students IN ROW EXCLUSIVE MODE; SELECT * FROM students WHERE id = 122 FOR UPDATE; UPDATE students SET type = 1 WHERE id = 122; END; In session 2 I concurrently run: UPDATE students SET type = type - 1 WHERE id = 122; The result I get is an exception, i.e student's type can't be lower than 1 in

问题 I want to make a new table in my database (Oracle 11g but the Express Edition for Ubuntu 16.04) using Python and Flask framework with the SQLAlchemy module. The first field of the table it's and ID, is an Integer field and I want it to autoincrement, but Oracle database don't support the autoincrement. I have a form to add a new comment, but when I try to add a new record it reports a error: sqlalchemy.exc.IntegrityError: (cx_Oracle.IntegrityError) ORA-01400: cannot insert NULL into ("WIKTOR"

问题 I'm using flask-marshmallow (marshmallow=v3.0.0rc1, flask-marshmallow=0.9.0) and flask-sqlalchemy (sqlalchemy=1.2.16, flask-sqlalchemy=2.3.2) I have this model and schema. from marshmallow import post_load, fields from .datastore import sqla_database as db from .extensions import marshmallow as ma class Study(db.Model): _id = db.Column(db.Integer, primary_key=True) name = db.Column(db.String, nullable=False) tests = db.relationship("Test", backref="study", lazy='select', cascade="all, delete