python - 使用sqlalchemy操作mysql，如何获取随机几项？

Question

users_query = db_session.query(User).filter(
    ~User.id.in_(followed_user_ids),
    User.status.in_([User.STATUS_NORMAL, User.STATUS_SUPER])
)

用.all()的话，结果太多了，我只想随机要5项，怎么写呢？

查了下stackoverflow已经解决：
http://stackoverflow.com/search?q=sqlalchemy+random

users = users_query.order_by(func.rand()).limit(5)

Answer 1

5 random items, or the first 5 items?

If it’s the first five items, it’s relatively simple:

users_query = db_session.query(User).filter(
    ~User.id.in_(followed_user_ids),
    User.status.in_([User.STATUS_NORMAL, User.STATUS_SUPER])
).limit(5).all()

If it is 5 random items, add something:

from  sqlalchemy.sql.expression import func

users_query = db_session.query(User).filter(
    ~User.id.in_(followed_user_ids),
    User.status.in_([User.STATUS_NORMAL, User.STATUS_SUPER])
).order_by(func.random()).limit(5).all()