Re: [HACKERS] Re: [INTERFACES] retrieving varchar size

>
> Byron Nikolaidis wrote:
> >
> > Hello,
> >
> > I was wondering if it would be possible, in the Postgres backend, to
> > send back the defined column size for the varchar data type (and
> > possibly the char() type, i.e., bpchar) on a query?  Currently, it just
> > sends back -1 for the size, which makes it difficult in the frontend
> > (i.e., odbc driver) to determine what the size of the column is.
>
> While the right solution to this is of course getting the size from
> backend, there exists a workaround now (assuming that the query is not
> too expensive). While ASCII cursors always hide the varchar sizes,
> binary ones return the size in actual data (by zero-padding the
> returned data to max size), so one can determine the actual max
> sizes by opening the query in binary cursor and then examining
> enough records to get one non-null field for each varchar field.

As of 6.3, this is only true of char() fields.  Varchar() is now
variable length.

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