howachen@gmail.com wrote:
> is this part of the ANSI SQL standard?

No, it is not part of the SQL standard.

Display-width does not constrain the range of input values for the
column, but it can be used when formatting text output.

It's possible that books misunderstand what the purpose of this optional
display-width argument is. Perhaps they're confusing it with the
precision and scale arguments to the DECIMAL type, which do affect the
values the column can store.

The display-width feature may not be something you need, but it is a
generalization to say that it is useless.

Regards,
Bill K.