python data_error ai_generated true

sqlalchemy.exc.InvalidRequestError: Session is already flushing

ID: python/flask-sqlalchemy-session-scope

Also available as: JSON · Markdown · 中文
80%Fix Rate
84%Confidence
0Evidence
2024-03-22First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
3.x active — — —

Root Cause

Trying to commit or flush a session while it's already in the process of flushing, often due to nested transactions.

generic

中文

在会话已经在刷新过程中尝试提交或刷新，通常由于嵌套事务导致。

Workarounds

  1. 95% success 
    Ensure one commit per request: use Flask-SQLAlchemy's teardown to remove session.
from flask_sqlalchemy import SQLAlchemy
db = SQLAlchemy(app)
# In route: db.session.add(obj); db.session.commit() only once
  2. 85% success 
    Use session.begin_nested() for subtransactions and commit at end.

Dead Ends

Common approaches that don't work:

  1. 80% fail

    Exacerbates nested transaction issues.

  2. 60% fail

    May lose changes and not solve the underlying concurrency issue.