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<p>我有下表:</p>
<pre><code>class Feedback(Base):
__tablename__ = 'feedbacks'
__table_args__ = (UniqueConstraint('user_id', 'look_id'),)
id = Column(Integer, primary_key=True)
user_id = Column(Integer, ForeignKey('users.id'), nullable=False)
look_id = Column(Integer, ForeignKey('looks.id'), nullable=False)
</code></pre>
<p>我目前正在向这个表中插入很多条目,这将违反UniqueConstraint。在</p>
<p>我使用以下代码:</p>
^{pr2}$
<p>我得到了以下错误:</p>
<pre><code>IntegrityError (IntegrityError) duplicate key value violates unique constraint "feedbacks_user_id_look_id_key"
DETAIL: Key (user_id, look_id)=(140, 263008) already exists.
'INSERT INTO feedbacks (user_id, look_id, score) VALUES (%(user_id)s, %(look_id)s, %(score)s) RETURNING feedbacks.id' {'user_id': 140, 'score': 1, 'look_id': 263008}
IntegrityError (IntegrityError) duplicate key value violates unique constraint "feedbacks_user_id_look_id_key"
...
(there's about 24 of these integrity errors here)
...
DETAIL: Key (user_id, look_id)=(173, 263008) already exists.
'INSERT INTO feedbacks (user_id, look_id, score) VALUES (%(user_id)s, %(look_id)s, %(score)s) RETURNING feedbacks.id' {'user_id': 173, 'score': 1, 'look_id': 263008}
No handlers could be found for logger "sqlalchemy.pool.QueuePool"
Traceback (most recent call last):
File "load.py", line 40, in <module>
load_crawl_data_into_feedback()
File "load.py", line 21, in load_crawl_data_into_feedback
for comment in session.query(Comment).filter(Comment.type == Comment.TYPE_LOOK).yield_per(100):
File "/Volumes/Data2/Dropbox/projects/Giordano/venv/lib/python2.7/site-packages/sqlalchemy/orm/query.py", line 2337, in instances
fetch = cursor.fetchmany(self._yield_per)
File "/Volumes/Data2/Dropbox/projects/Giordano/venv/lib/python2.7/site-packages/sqlalchemy/engine/base.py", line 3230, in fetchmany
self.cursor, self.context)
File "/Volumes/Data2/Dropbox/projects/Giordano/venv/lib/python2.7/site-packages/sqlalchemy/engine/base.py", line 3223, in fetchmany
l = self.process_rows(self._fetchmany_impl(size))
File "/Volumes/Data2/Dropbox/projects/Giordano/venv/lib/python2.7/site-packages/sqlalchemy/engine/base.py", line 3343, in _fetchmany_impl
row = self._fetchone_impl()
File "/Volumes/Data2/Dropbox/projects/Giordano/venv/lib/python2.7/site-packages/sqlalchemy/engine/base.py", line 3333, in _fetchone_impl
self.__buffer_rows()
File "/Volumes/Data2/Dropbox/projects/Giordano/venv/lib/python2.7/site-packages/sqlalchemy/engine/base.py", line 3326, in __buffer_rows
self.__rowbuffer = collections.deque(self.cursor.fetchmany(size))
sqlalchemy.exc.ProgrammingError: (ProgrammingError) named cursor isn't valid anymore None None
</code></pre>
<p>在你下结论说这个错误是由收益率引起的之前,我可以向你保证收益率不是这里的罪魁祸首。在</p>
<p>我在没有唯一约束的情况下尝试了相同的代码,并且没有遇到任何错误。在</p>
<p>我认为完整性错误导致<strong>找不到记录器的处理程序“sqlalchemy.pool.QueuePool“</strong>。在</p>
<p>我假设每个完整性错误都会杀死队列池中的每个“线程”。在</p>
<p>有人能告诉我发生了什么事吗?在</p>
<p>如果我在这一点上不能做太多的数据,你会建议我做什么?在</p>