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ORA-01407: Cannot update (column) to NULL
What it means
An UPDATE set a NOT NULL column to NULL, typically through a correlated subquery that found no row for some target rows.
How to fix it
Add WHERE EXISTS (same subquery) to the UPDATE, or use NVL/COALESCE in the SET, or rewrite as MERGE.
Catch it before it runs
ORA Error Helper
Explains ORA-/PLS- codes inside JetBrains IDEs and DataGrip. PL/SQL Lint
Flags risky PL/SQL patterns while you type. Oracle Plan Reader
Reads execution plans and points at the slow step. PL/SQL in Practice
Kindle book with practical PL/SQL for working developers.
Explains ORA-/PLS- codes inside JetBrains IDEs and DataGrip. PL/SQL Lint
Flags risky PL/SQL patterns while you type. Oracle Plan Reader
Reads execution plans and points at the slow step. PL/SQL in Practice
Kindle book with practical PL/SQL for working developers.
Nearby errors
Updated 2026-11-12.