How to fix the Oracle error QSM-02003: aggregate function nested within an expression?

In this post, you’ll learn more about the Oracle ErrorQSM-02003: aggregate function nested within an expression with the details on why you receive this error and the possible solution to fix it.

Oracle Error Description

QSM-02003: aggregate function nested within an expression

Reason for the Error QSM-02003: aggregate function nested within an expression

The capability in question is not supported when the materialized view contains an aggregate function invocation nested within an outer expression.

How to fix the Error QSM-02003: aggregate function nested within an expression ?

You can fix this error in Oracle by following the below steps

Re-phrase the expression such that the aggregate function invocation is not nested.