dify/api/extensions/ext_database.py

from flask_sqlalchemy import SQLAlchemy
from sqlalchemy import MetaData

POSTGRES_INDEXES_NAMING_CONVENTION = {
    'ix': '%(column_0_label)s_idx',
    'uq': '%(table_name)s_%(column_0_name)s_key',
    'ck': '%(table_name)s_%(constraint_name)s_check',
    'fk': '%(table_name)s_%(column_0_name)s_fkey',
    'pk': '%(table_name)s_pkey',
}

metadata = MetaData(naming_convention=POSTGRES_INDEXES_NAMING_CONVENTION)
db = SQLAlchemy(metadata=metadata)


def init_app(app):
    db.init_app(app)