[Regression] Redshift intermittent error “could not complete because of conflict with concurrent transaction” #12334
Description
Is this a regression in a recent version of dbt-core?
- I believe this is a regression in dbt-core functionality
- I have searched the existing issues, and I could not find an existing issue for this regression
Current Behavior
Very similar to what's described in dbt-labs/dbt-adapters#626 from 2024, but our issue started around the release of dbt-core v1.11.
We’re using dbt cloud, with a Redshift Serverless warehouse. We have been running scheduled dbt jobs with 4 threads for months without an issue.
Starting December 19, 2025 (which is the release date of dbt core v1.11), we started having intermittent dbt job failures, with the error:
could not complete because of conflict with concurrent transaction
This always happens on the same model (dim_country), which is among the first 4 models to be processed by our 4-thread job. The materialization mode is table.
We have ruled out external conflicts (with other jobs, processes or manual queries) - this errors occurs when nothing else is using this table. The only queries running in parallel are the models processed by the other threads of the same job.
When reviewing the debug logs, we see that the failed statement is always the following:
drop table if exists "dw"."models"."dim_country__dbt_backup" cascade;
The jobs are always scheduled on a round hour (6am, 6pm). We have tried changing to 3am but the issue persists.
When manually re-running the failed jobs, they always complete successfully.
Expected/Previous Behavior
Models running with multiple threads and not facing conflict errors.
Steps To Reproduce
Same as described in this dbt-labs/dbt-adapters#626.
Relevant log output
Environment
Using dbt cloudWhich database adapter are you using with dbt?
redshift
Additional Context
No response