All errors › ORA errors
ORA-00001: Unique constraint violated
What it means
An INSERT or UPDATE tried to store a value that already exists in a column (or column set) protected by a PRIMARY KEY or UNIQUE constraint or a unique index. The error text names the constraint (owner.constraint_name).
How to fix it
Find the constraint: SELECT table_name, column_name FROM all_cons_columns WHERE constraint_name = '<name>'. Then check for the existing row, use a sequence/identity for generated keys, or use MERGE when the row may already exist. In bulk loads, DML error logging (LOG ERRORS INTO) lets the good rows through.
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.