ORA-00909: Invalid Number of Arguments — Causes, Fixes, and Prevention
ORA-00909 is a parse-time error thrown by Oracle Database when a built-in or user-defined function is called with the wrong number of arguments. Because it occurs during the SQL parsing phase — before any data is actually accessed — the query fails immediately and no rows are returned. This error is common among developers who work across multiple database platforms or those who call PL/SQL functions whose signatures have changed.
Top 3 Causes
1. Wrong Argument Count for a Built-in Function
The most frequent cause is simply passing too few or too many arguments to Oracle built-in functions like NVL, SUBSTR, ROUND, or DECODE.
