Ok, I am new to SQL Server and DBs and I tried the following

INSERT INTO db2..mytext (Spanish)

SELECT Spanish FROM db1..mytext

However, I get the following error message:

Cannot insert the value NULL into column 'ID', table 'db2.dbo.mytext'; column does not allow nulls. INSERT fails.

The statement has been terminated.

ID is the primary key and is filled with numbers. Any ideas?