Re: AW: Tables and PFs

There are exceptions to that rule also. Writes to a table created with
DDS can be validated at write time and not wait until read. You just have
to use "newer" type fields like dates and times. Example: You cannot
create a pf with a date field in it using DDS and then use CPYF from a
"flat" file to put invalid data into the date field like you can with a
DDS file containing packed numbers and whatnot. I suspect this was done
for backward compatibility with software that might have had a column
defined as packed and some purchaser of the application used a data
structure or something to store alpha data in there because they never
used the originally intended use of the numeric column. More of an
example, if the column was Zimbabwe tax rate and you don't do business
there you might use it to store an alpha grouping class or some such
thing. And IBM probably felt that, if you defined the table using SQL
then it probably doesn't have any of those backward compatibility things
to worry about so they could enforce that the data really was numeric on a
write there.

Now, in DDS, just the newer type fields are validated at write - you can
still screw up the rest of the columns.


Rob Berendt