SQL Server Error 547 — Why Foreign Key Rejects, and Which Row Is at Fault?
Diagnosing SQL Server Error 547 Foreign Key violations, finding orphan rows, why WITH CHECK is mandatory after NOCHECK to prevent is_not_trusted=1, and bulk loading sequencing.
Operational Verification & Reliability Metadata
The error string is a symptom, not the root cause. Do not restart the server blindly. Run the diagnostic queries below to pinpoint the actual failure mode.
▸Symptoms
The INSERT statement conflicted with the FOREIGN KEY constraint "FK_Siparis_Musteri".
The conflict occurred in database "app", table "dbo.Musteri", column 'Id'.▸Diagnosis & Resolution
- 1Inspect Constraint Trust State:
SELECT name, is_disabled, is_not_trusted
FROM sys.foreign_keys WHERE name = 'FK_Siparis_Musteri';If is_not_trusted = 1, SQL Server optimizer cannot use this constraint for join elimination.
- 1Locate Orphan Rows:
SELECT c.* FROM dbo.Siparis c
LEFT JOIN dbo.Musteri p ON p.Id = c.MusteriId
WHERE c.MusteriId IS NOT NULL AND p.Id IS NULL;- 1Re-enable with WITH CHECK:
ALTER TABLE dbo.Siparis WITH CHECK CHECK CONSTRAINT FK_Siparis_Musteri;- •Companion Guide (MySQL): MySQL Error 1452 Foreign Key
- •Engine Hub: SQL Server Production Hub
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