All errors › ORA errors
ORA-01722: Invalid number
What it means
A string could not be converted to a number. Very often caused by implicit conversion: comparing a VARCHAR2 column holding some non-numeric values with a number (WHERE code = 123), so the error depends on the execution plan and data.
How to fix it
Compare strings with strings (WHERE code = '123'), or convert safely with TO_NUMBER(x DEFAULT NULL ON CONVERSION ERROR) (12.2+) / VALIDATE_CONVERSION. Check NLS decimal separator for values like '1,5'.
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.