python data_error ai_generated true

sqlalchemy.orm.exc.StaleDataError: UPDATE statement on table 'users' expected to update 1 row(s); Only 0 were matched.

ID: python/sqlalchemy-stale-data-issue

Also available as: JSON · Markdown · 中文
80%Fix Rate
85%Confidence
0Evidence
2024-10-01First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
3.x active — — —

Root Cause

Optimistic concurrency control: row was modified or deleted by another transaction.

generic

中文

乐观并发控制：行被其他事务修改或删除。

Workarounds

  1. 90% success Refresh object before update. 
    session.refresh(user)
user.name = 'new_name'
session.commit()
  2. 85% success Use version counter in model. 
    class User(Base):
    __tablename__ = 'users'
    id = Column(Integer, primary_key=True)
    version_id = Column(Integer, nullable=False)
    __mapper_args__ = {'version_id_col': version_id}

Dead Ends

Common approaches that don't work:

  1. Ignoring the error and retrying without refresh. 80% fail

    Stale object leads to further inconsistencies.

  2. Disabling versioning entirely. 60% fail

    Loses concurrency protection; data corruption possible.