The reason is simple - as you need the artificial PK lpp_id, then
everything else becomes an constraint
Thanks,
Anton
On Jul 24, 2013, at 0:28, JORGE MALDONADO jorgemal1...@gmail.com wrote:
In your case it would be lpp_id as PK, and
lpp_person_id,lpp_language_id as unique constraint
Agreed with Anton, as PK, lpp_id is easier to be managed than (lpp_person_id
+ lpp_language_id)
One more suggestion, foreign key constraints could be setup on lpp_person_id
and lpp_language_id to link with target tables.
Thanks,
Stan
2013/7/24 Anton Gavazuk antongava...@gmail.com
The reason
Hi,
I also need the field lpp_id as a unique key which is a field that
contains a consecutive number of type serial.
Are you sure you REALLY need this? It looks like a lot of trouble for
nothing, as you now have one thing warranting the unicity of the record
(your serial) plus a unique key
On Wed, Jul 24, 2013 at 10:38 AM, Bèrto ëd Sèra berto.d.s...@gmail.com wrote:
What would be the rationale behind the serial number?
The serial key, also named surrogate key is there for management
purposes. Imagine one day you find out your database design is wrong
and what was unique the day
Hi,
It looks heavy, performance-wise. If this is not OLTP intensive you can
probably survive, but I'd still really be interested to know ow you can end
up having non unique records on a Cartesian product, where the PK is
defined by crossing the two defining tables. Unless you take your PK down
On Wed, Jul 24, 2013 at 11:47 AM, Bèrto ëd Sèra berto.d.s...@gmail.com wrote:
Hi,
It looks heavy, performance-wise. If this is not OLTP intensive you can
probably survive, but I'd still really be interested to know ow you can end
up having non unique records on a Cartesian product, where the
Hi,
yeah, I am okay with design prudence, just used to be so paranoid about
performance that just any possible one more thing to do gets me nervous
:) Language versions do exist, say Dutch has different orthography
depending on what convention is used, so you may well need to suddenly add
a
On Mon, Jul 8, 2013 at 2:18 PM, Andreas maps...@gmx.net wrote:
How could I combine those 2 queries so that the date in query 1 would be
replaced dynamically with the result of the series?
Surely I'm missing something, but maybe this is something to work on:
WITH
RECURSIVE months(number) AS
