Re: Inheritence and Integrity

From: chester c young <chestercyoung(at)yahoo(dot)com>
To: Neal Lindsay <neal(dot)lindsay(at)peaofohio(dot)com>
Cc: pgsql-sql(at)postgresql(dot)org
Subject: Re: Inheritence and Integrity
Date: 2003-01-30 06:27:07
Message-ID: 20030130062707.48883.qmail@web12703.mail.yahoo.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-sql

> inheriting pk and triggers

pg inheritance is quite limited. what i (and i'm sure many others)
have done is:

1. create master sequence
2. create base table
3. create base trigger procedures
4. create derived tables, using "inherit"
5. write procedure p( table_name ) that
a) sets pk of table_name using master sequence
b) attaches base trigger procedures onto table_name
6. run procedure p() against each derived table

another way to skin this cat is to use "objects" in the database:

-- base table
table common(
int id primary key ...,
ref_tab name, -- name of secondary table using common
... -- common columns and constraints
) without oids;

-- secondary table
table secondary1(
int id1 not null references common(id),
int id2 primary key, -- (can use id1 as pk!)
... -- secondary columns and constraints
) without oids;

-- views for secondary table - generate!
create secondary1_v1 as select c.*, s.*
from secondary1 s join common c on( s.id1 = c.id );

-- (if you want) dml for view to make life easier - generate!
...

if you are maintaining the common info, or if you want a many to one
secondary to master, this approach is easier.

__________________________________________________
Do you Yahoo!?
Yahoo! Mail Plus - Powerful. Affordable. Sign up now.
http://mailplus.yahoo.com

In response to

Browse pgsql-sql by date

  From Date Subject
Next Message Tony Simbine 2003-01-30 08:20:08 Re: help: triggers
Previous Message Ryan 2003-01-29 21:30:11 Re: double linked list