How to resolve ORA-01012 Error Message in Oracle database

Learn the cause and how to resolve the ORA-01012 error message in Oracle.

Description

When you come across an ORA-01012 error, the following error message will appear:

ORA-01012: not logged on

Cause

You tried to execute a call to Oracle before logging in.

Resolution

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

Option #1

Log onto Oracle by calling OLON or OLOGON.