Limits for the nchar(n) data type, where (n) is the numeric character length, are summarized in the following table. The gateway requires the length to be explicitly specified. If length is not specified, it will trigger a gateway syntax error. This differs from the Ingres DBMS, which defaults the length to 1 if it is not specified. For detailed information about individual gateways, see the sections that follow.

Nchar(n) returned from row returning/producing procedures/functions in Oracle are blank padded. With Ingres, they are not blank padded.