Hello Eric B,
Thank you for posting your question in the Microsoft Q&A forum.
The intermittent 500 and 400 errors in your Database API Builder (DAB) across multiple Static Web Apps (SWA) instances suggest either a service disruption or configuration issue. First, check Azure Status for any ongoing incidents with DAB or dependent services.
Key troubleshooting steps:
- Verify your connection strings and database permissions haven't expired or changed
- Review recent deployment logs for schema changes that might conflict with DAB
- Test with a minimal API endpoint to isolate whether the issue affects all endpoints
If basic checks show no problems, redeploy your DAB configuration and enable detailed logging to capture the root cause. The mixed error codes often indicate either authentication problems (400) or backend processing failures (500).
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