Re: Other attributes besides type,precision,scale

On Wed, 30 Mar 2005 18:04:32 -0500, Kenneth Downs <knode.wants.this_at_see.sigblock> wrote:

>I'm curious about the terms used to describe extended properties of a column
>definition.
>
>In this particular instance, we are flagging that some columns contain the
>value of a URL. The UI code will see this and convert the values to
>hyperlinks where appropriate.
>
>There are a few ways to do this. We might allow a column type called URL
>that is implemented as an x-digit varchar, with various extra validation

                             ^^^^^
     You mean "character"?

>and special treatment by the UI. A data dictionary entry for the table
>might then look like:

>table vendors {
> column company_name { type: varchar; precision: 40 }
> column website { type: url } [Quoted]
> ...other columns...
>}

     That looks fine to me.

>The other option is to keep the types more pure and add a flag to the column
>definition, which is then interpreted where appropriate by the various
>tiers, so that we define the column as:
>
>column website { type: varchar; precision: 40; url: yes }

     You are jumbling URLs and non-URLs together. This is LESS pure!

>and the table as:
>
>table vendors {
> column company_name { type: varchar; precision: 40 }
> column website
>}

>A first glance reaction might be to say, "nonsense, it's pure UI, keep it
>out of the data dictionary!" But we also define the URL's for XML RPC
>calls in data, and then we define columns in terms of the return values
>from XML RPC calls, so the URL there is part of automated processes, not
>just UI.

     My glance does not react that way. If you need that sort of data stored, put it in your database.

>Anyway, any thoughts are always welcome.

Sincerely,

Gene Wirchenko Received on Tue Apr 05 2005 - 18:22:29 CEST