from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy import MetaData

# 推荐命名约定以避免冲突
metadata = MetaData(
    naming_convention={
        "ix": "ix_%(column_0_label)s",
        "uq": "uq_%(table_name)s_%(column_0_name)s",
        "ck": "ck_%(table_name)s_%(constraint_name)s",
        "fk": "fk_%(table_name)s_%(column_0_name)s_%(referred_table_name)s",
        "pk": "pk_%(table_name)s"
    }
)

Base = declarative_base(metadata=metadata)
