referencing oracle table thru foreign key
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I attempting to alter my table.  However, it's giving me an error.  I am very new to DB.

I have a table name called dept_email and col names are
Dept
email

Anoter table name called dept and col names are
Code
Description
Abbreviation
password

I have genereate a foreign key with dept (abbreviation) to dept_email(dept).  I am totally lost at this point.  Can anyone please help me to understand this.  THANKS IN ADVANCE!