How to resolve ORA-01843 Error Message in Oracle database

Learn the cause and how to get to the bottom of the ORA-01843 error message in Oracle.

Description

When you come upon an ORA-01843 error, the following error message will appear:

ORA-01843: not a valid month

Cause

You entered a date, but the month element of the date was not a legitimate month.

Resolution

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

Option #1

Re-enter the date cost using both a MONTH format mask.

The valid values for month are:

January February March April May June July August September October November December

Or you may want to use the MON structure mask and use one of the following values:

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

If all else fails, you may want to consider using the TO_DATE characteristic and specifying the date format mask.