Re: surrogate vs natural primary keys

Hi,

After some more reading and considering your feedback, I'm still
somewhat confused about this issue.

1. Should the choice of surrogate/natural primary keys be done across an
entire database, or does it make more sense to do it on a per-table
basis? I reckon one could do it on a per-table basis, but its direct
relationships would influence the choice.

2. If we do find a suitable natural primary key for a table, but it
turns out to be a composite one, how can such a key be referred to in
another table? Say we have:

CREATE TABLE t1 (
c1 varchar(200),
c2 int8,
c3 varchar(500),
PRIMARY KEY (c1, c2)
);

and I want to create a table t2 which needs to refer to the composite
primary key of t1. Should one create 2 columns in t2 that REFERENCE c1
and c2? If so, this seems very cumbersome and I'm tempted to create a
surrogate key in t1 just to be able to refer to it more efficiently. Is
this something we should be considering when choosing natural
vs. surrogate keys? Thanks again.

--
Seb