Oracle / PLSQL: ORA-00960 Error Message

Learn the cause and how to resolve the ORA-00960 error message in Oracle.

Description

When you encounter an ORA-00960 error, the following error message will appear:

• ORA-00960: ambiguous column naming in select list

Cause

You tried to execute a SELECT statement where a column with the same name is listed in the SELECT list and then ambiguously defined within the ORDER BY clause.

Resolution

The option(s) to resolve this Oracle error are:

Option #1

Try prefixing the column that is ambiguously defined in the ORDER BY clause with the table name.

For example, if you tried to execute the following SELECT statement:

SELECT suppliers.supplier_id, orders.supplier_id
FROM suppliers
INNER JOIN orders
ON suppliers.supplier_id = orders.supplier_id
ORDER BY supplier_id;

You would receive the following error message:

You could correct this error by prefixing the supplier_id column in the ORDER BY clause with either supplier or orders.

For example:

SELECT suppliers.supplier_id, orders.supplier_id
FROM suppliers
INNER JOIN orders
ON suppliers.supplier_id = orders.supplier_id
ORDER BY suppliers.supplier_id;

OR

SELECT suppliers.supplier_id, orders.supplier_id
FROM suppliers
INNER JOIN orders
ON suppliers.supplier_id = orders.supplier_id
ORDER BY orders.supplier_id;