［已解决］SQLAlchemy中如何得到db.session.commit后的新增的对象

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期间，对于已有的代码：

/Users/crifan/dev/dev_root/daryun/SIPEvents/sourcecode/sipevents/sipevents/models.py

class Event(db.Model):

__tablename__ = “events”

# Columns

id = db.Column(db.Integer, primary_key = True, autoincrement = True, nullable=False)

#user_openid = db.Column(db.String(64))

#user_openid = db.Column(db.String(64), db.ForeignKey(‘user.openid’))

user_openid = db.Column(db.String(64), db.ForeignKey(‘wechat_users.openid’))

title = db.Column(db.String(128))

start_date = db.Column(db.DateTime)

end_date = db.Column(db.DateTime)

location = db.Column(db.String(256))

cur_user_num = db.Column(db.Integer)

max_user_num = db.Column(db.Integer)

is_public = db.Column(db.Boolean)

description = db.Column(db.Text)

notification_time = db.Column(db.Enum(NotificationTime))

# joiners = db.relationship(‘EventJoiner’, backref=’user’, lazy=’dynamic’)

#joiners = db.relationship(‘User’, secondary = event_joiners, backref=’events’)

#joiners = db.relationship(‘User’, secondary=event_joiners, backref=’joined_events’,lazy=’dynamic’)

joiners = db.relationship(‘User’, secondary=event_joiners, backref=’joined_events’)

def __init__(self,

# id,

user_openid,

title = “”,

location = “”,

start_date = None,

end_date = None,

cur_user_num = 0,

max_user_num = 0,

is_public = False,

description = “”,

notification_time = NotificationTime.NotNotify):

# self.id = id

self.user_openid = user_openid

self.title = title

self.location = location

self.start_date = start_date

self.end_date = end_date

self.cur_user_num = cur_user_num

self.max_user_num = max_user_num

self.is_public = is_public

self.description = description

self.notification_time = notification_time

def __repr__(self):

#return u'<Event id=%d user_openid=%s title=%r>’ % (self.id, self.user_openid, self.title)

return u'<Event id=%s user_openid=%s title=%r>’ % (self.id, self.user_openid, self.title)

/Users/crifan/dev/dev_root/daryun/SIPEvents/sourcecode/sipevents/sipevents/views.py

newEvent = Event(user_openid = curUser.openid,

title = title,

location = location,

start_date = startDate,

end_date = endDate,

cur_user_num = 1,

max_user_num = maxUserNum,

is_public = is_public,

description = description,

notification_time = notificationTimeEnum)

gLog.debug(‘newEvent=%s’, newEvent)

#add self to joiners

gLog.debug(“type(curUser)=%s, curUser=%s”, curUser, type(curUser))

newEvent.joiners.append(curUser)

gLog.debug(‘added self to joiners, newEvent=%s’, newEvent)

db.session.add(newEvent)

db.session.commit()

gLog.debug(“added new event=%s”, newEvent)

希望实现：

在

db.session.add(newEvent)

以及：

db.session.commit()

之后，可以得到对应的这个新的event的对象

注：此处的newEvent变量，是提交之前的，其id是为空的

sqlalchemy get object after commit

python – sqlalchemy flush() and get inserted id? – Stack Overflow

db.session.add(newEvent)

db.session.refresh(newEvent)

db.session.commit()

搜：

sqlalchemy session refresh flush

Session API — SQLAlchemy 1.1 Documentation

“

flush(objects=None)

Flush all the object changes to the database.

Writes out all pending object creations, deletions and modifications to the database as INSERTs, DELETEs, UPDATEs, etc. Operations are automatically ordered by the Session’s unit of work dependency solver.

Database operations will be issued in the current transactional context and do not affect the state of the transaction, unless an error occurs, in which case the entire transaction is rolled back. You may flush() as often as you like within a transaction to move changes from Python to the database’s transaction buffer.

For autocommit Sessions with no active manual transaction, flush() will create a transaction on the fly that surrounds the entire set of operations into the flush.

Parameters:

objects –

Optional; restricts the flush operation to operate only on elements that are in the given collection.

This feature is for an extremely narrow set of use cases where particular objects may need to be operated upon before the full flush() occurs. It is not intended for general use.

refresh(instance, attribute_names=None, lockmode=None)¶

Expire and refresh the attributes on the given instance.

A query will be issued to the database and all attributes will be refreshed with their current database value.

Lazy-loaded relational attributes will remain lazily loaded, so that the instance-wide refresh operation will be followed immediately by the lazy load of that attribute.

Eagerly-loaded relational attributes will eagerly load within the single refresh operation.

Note that a highly isolated transaction will return the same values as were previously read in that same transaction, regardless of changes in database state outside of that transaction – usage ofrefresh() usually only makes sense if non-ORM SQL statement were emitted in the ongoing transaction, or if autocommit mode is turned on.

Parameters:

attribute_names – optional. An iterable collection of string attribute names indicating a subset of attributes to be refreshed.
lockmode – Passed to the Query as used by with_lockmode().

［已解决］SQLAlchemy中如何得到db.session.commit后的新增的对象

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