如何在flask sqlAlchemy中配置sqlAlchemy不创建表？
我只使用flask-sqlalchemy Model的特性，但不会创建表格。
如何配置？
因为我要在sql View中使用，所以如果运行db.create_all()，View就变成了表。
谢谢。
这是一个视图！
代码语言：javascript复制# -*- coding: utf-8 -*-
from settings.dataBase import CRUDMixin, db
class ViewExample(db.Model, CRUDMixin):
__tablename__ = "view_example"
id = db.Column(db.Integer, primary_key=True, nullable=False)
name = db.Column(db.String(50))
title = db.Column(db.String(100))
is_albums = db.Column(db.Integer)
is_attach = db.Column(db.Integer)
is_spec = db.Column(db.Integer)
sort_id = db.Column(db.Integer)
def __init__(self, **kwargs):
for key, value in kwargs.items():
setattr(self, key, value)
def __str__(self):
return 'id : %s' % self.id我找到了一个例子，但我不知道如何在flask-sqlalchemy中使用。alembic slqlalchemy文档：https://alembic.sqlalchemy.org/en/latest/cookbook.html#don-t-emit-create-table-statements-for-views
flask-migrate env.py我添加了一个include_object函数，但没有获得is_view。
代码语言：javascript复制from __future__ import with_statement
import logging
from logging.config import fileConfig
from sqlalchemy import engine_from_config
from sqlalchemy import pool
from alembic import context
# this is the Alembic Config object, which provides
# access to the values within the .ini file in use.
config = context.config
# Interpret the config file for Python logging.
# This line sets up loggers basically.
fileConfig(config.config_file_name)
logger = logging.getLogger('alembic.env')
# add your model's MetaData object here
# for 'autogenerate' support
# from myapp import mymodel
# target_metadata = mymodel.Base.metadata
from flask import current_app
config.set_main_option(
'sqlalchemy.url', current_app.config.get(
'SQLALCHEMY_DATABASE_URI').replace('%', '%%'))
target_metadata = current_app.extensions['migrate'].db.metadata
# other values from the config, defined by the needs of env.py,
# can be acquired:
# my_important_option = config.get_main_option("my_important_option")
# ... etc.
def include_object(object, name, type_, reflected, compare_to):
"""
Exclude views from Alembic's consideration.
"""
print(object.info)
return not object.info.get('is_view', False)
def run_migrations_offline():
"""Run migrations in 'offline' mode.
This configures the context with just a URL
and not an Engine, though an Engine is acceptable
here as well. By skipping the Engine creation
we don't even need a DBAPI to be available.
Calls to context.execute() here emit the given string to the
script output.
"""
url = config.get_main_option("sqlalchemy.url")
context.configure(
url=url, target_metadata=target_metadata, literal_binds=True,
)
with context.begin_transaction():
context.run_migrations()
def run_migrations_online():
"""Run migrations in 'online' mode.
In this scenario we need to create an Engine
and associate a connection with the context.
"""
# this callback is used to prevent an auto-migration from being generated
# when there are no changes to the schema
# reference: http://alembic.zzzcomputing.com/en/latest/cookbook.html
def process_revision_directives(context, revision, directives):
if getattr(config.cmd_opts, 'autogenerate', False):
script = directives[0]
if script.upgrade_ops.is_empty():
directives[:] = []
logger.info('No changes in schema detected.')
connectable = engine_from_config(
config.get_section(config.config_ini_section),
prefix='sqlalchemy.',
poolclass=pool.NullPool,
)
with connectable.connect() as connection:
context.configure(
connection=connection,
target_metadata=target_metadata,
include_object=include_object,# add
process_revision_directives=process_revision_directives,
**current_app.extensions['migrate'].configure_args
)
with context.begin_transaction():
context.run_migrations()
if context.is_offline_mode():
run_migrations_offline()
else:
run_migrations_online()添加__table_args__ = { "info": dict(is_view=True)}是很好的。
代码语言：javascript复制class ViewExample(db.Model, CRUDMixin):
__tablename__ = "view_example"
__table_args__ = { "info": dict(is_view=True)} # add 谢谢!这个问题已经解决了。