UnicodeEncodeError: 'latin-1' codec can't encode characters in position 0-1: ordinal not in range(256)

SQLAlchemy insert error

db = create_engine('mysql://user:pass@localhost/db?charset=utf8')

References :
python - How do I get SQLAlchemy to correctly insert a unicode ellipsis into a mySQL table? - Stack Overflow 

RuntimeError: application not registered on db instance and no application bound to current context

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

References :
python - When scattering Flask Models, RuntimeError: 'application not registered on db' was raised - Stack Overflow

SQLAlchemy use unicode

engine = create_engine('mysql://root:password@localhost/test?charset=utf8&use_unicode=0')

References :
sqlalchemy中文问题解决方案 - 江湖 - 51CTO技术博客

SQLAlchemy query where not null

seats = Seat.query.filter(Seat.invite != None).all()

References : 

ython - flask sqlalchemy querying a column with not equals - Stack Overflow

application not registered on db instance and no application bound to current context

直接使用 db.create_all() 會出錯，改成以下

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

問題說明：
Flask and SQLAlchemy: init_app · Piotr Banaszkiewicz




References :
python - When scattering Flask Models, RuntimeError: 'application not registered on db' was raised - Stack Overflow

OpenShift SQLAlchemy Database URI

PostgreSQL :

import os
SQLALCHEMY_DATABASE_URI = os.environ['OPENSHIFT_POSTGRESQL_DB_URL']

MySQL :

import os
SQLALCHEMY_DATABASE_URI = os.environ['OPENSHIFT_MYSQL_DB_URL']

References :
flask程序部署在openshift上的一些注意事项 - ranvane的个人空间 - 开源中国社区

Sqlalchemy delete in subquery

InvalidRequestError: Could not evaluate current criteria in Python. Specify 'fetch' or False for the synchronize_session parameter.

sl = DBSession.query(Puesto.id).filter(Puesto.locales_id == id).subquery() DBSession.query(Servicio).filter(Servicio.puestos_id.in_(sl)) \ .delete(synchronize_session='fetch')

References :
python - Sqlalchemy delete subquery - Stack Overflow

SQLAlchemy return insert id

user = db.session.execute(Users.__table__.insert(data))
db.session.commit()
print user.lastrowid

ImportError: No module named sqlalchemy

# pip install sqlalchemy

SQLAlchemy 沒有主鍵 錯誤

sqlalchemy.exc.ArgumentError: Mapper Mapper|FooTable|foo_table could not assemble any primary key columns for mapped table 'foo_table'


SQLAlchemy 不允許沒有定義主鍵，若是複合主鍵，則需要在多個欄位加上 primary_key=True。




References :
MooGoo's Blog: [SQLAlchemy] 不用primary key的table
SQLAlchemy0.6.5文檔-----用元數據定義數據庫_StackDoc

SQLAlchemy get table primary_key name

pri_key = (list(TabelClass.__table__.primary_key)[0]).name





References :
zzzeek : SQLAlchemy

FullText Search supported for SQLAlchemy

Reference :
SQLAlchemy-FullText-Search 0.2 : Python Package Index

ImportError: No module named MySQLdb

# apt-get install libmysqlclient-dev
# pip install MySQL-python

SQLAlchemy SELECT INNER JOIN

from sqlalchemy.orm import relation

owners = relation('User', order_by='User.id', uselist=True, backref='addresses')

from sqlalchemy.schema import Column, ForeignKey

address_id = Column(Integer, ForeignKey('addresses.id'))

Reference :
Python の O/Rマッパー SQLAlchemy を使ったリレーショナルマッピング基本 4 パターン | CUBE SUGAR STORAGE
python - SQLAlchemy Query foreignkey field(s) - Stack Overflow

SQLAlchemy SELECT WHERE NULL Values

query.where(user.name is None)




Reference :
Select NULL Values In SQLAlchemy | Verious

sqlalchemy multi columns/fields primary key

Table(
    'table_name', metadata,
    Column('id', None, nullable=False),
    Column('email', None, nullable=False),
    PrimaryKeyConstraint('id', 'email'),
)

Reference :

python - Creating container relationship in declarative SQLAlchemy - Stack Overflow

ImportError: cannot import name EXT_PASS

from sqlalchemy.orm import MapperExtension, EXT_PASS
ImportError: cannot import name EXT_PASS


use EXT_CONTINUE instead of EXT_PASS




Reference :
ImportError: cannot import name EXT_PASS - Google Groups

auto create, update time in sqlalchemy

Column('creation_date', DateTime, default=func.now()),
Column('last_modified', DateTime, onupdate=func.now()),