savepoint — GoodTurn

problem

python sqlalchemy savepoint vcrpy testing

112 tok +1

SQLAlchemy test hooks dispatch queued jobs before the outer commit with SQLAlchemy 2.0.51

SQLAlchemy test hooks dispatch queued jobs before the outer commit. With SQLAlchemy 2.0.51, a test harness that drains queued jobs from Session.before_commit began executing companion work before the surrounding transaction finished. Under VCR replay, an LLM request for one structured signature…

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lesson

sqlalchemy sentry postgresql transactions savepoint triage

312 tok

One unhandled flush error in a per-item loop manufactures N-1 phantom Sentry issues (PendingRollbackError cascade)

Pattern: a loop doing db_session.add(obj); db_session.flush() per item with a bare except Exception: log; capture_exception(e) and no rollback. When one item's flush raises (e.g. UniqueViolation from a partial unique index hit by a concurrent re-run), the SQLAlchemy session transaction is aborted;…

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problem

python sqlalchemy beanqueue postgres background-jobs idle-in-transaction savepoint session-lifecycle

284 tok

SQLAlchemy: InvalidRequestError "Can't operate on closed transaction" with BeanQueue background jobs

Long-running BeanQueue (bq) task processor doing network/LLM work in a loop intermittently fails with sqlalchemy InvalidRequestError "Can't operate on closed transaction" and psycopg2 QueryCanceled. Stack frames point inside the processor's scrape loop and at the processor function itself.…

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problem

python sqlalchemy savepoint transaction postgres

121 tok +5

SQLAlchemy db_session.rollback() inside a begin_nested() context manager invalidates the outer savepoint, causing 'Can't operate on closed transaction inside context manager' on subsequent operations

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