How to fix the Oracle error NID-00126: Database should have no datafiles in unknown state?

In this post, you’ll learn more about the Oracle ErrorNID-00126: Database should have no datafiles in unknown state with the details on why you receive this error and the possible solution to fix it.

Oracle Error Description

NID-00126: Database should have no datafiles in unknown state

Reason for the Error NID-00126: Database should have no datafiles in unknown state

The database has one or more datafiles that are in an unknown state.

How to fix the Error NID-00126: Database should have no datafiles in unknown state ?

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

Drop the datafiles or recover them and bring them online.