Re: one more word about rules (fwd) - Mailing list pgsql-general

From John McKown
Subject Re: one more word about rules (fwd)
Date
Msg-id Pine.LNX.4.21.0009221435400.12255-100000@linux2.johnmckown.net
Whole thread Raw
List pgsql-general
Well, how about just adding something other than 1 (such as 100) to the
value in the table? As for the existing table, perhaps, before moving it
to the new table, you could do something like:

UPDATE table SET article_number=article_number*100;

This would change all the current article numbers to higher values. If
these numbers are referenced in other columns, then do an equivalent
UPDATE command on those columns as well.

This is about all that I can come up with.

John

On Fri, 22 Sep 2000, Abe Asghar wrote:

> John,
>
> The way I generate my article number is by having a table called unique_key.
> This table holds a number that is read and 1 is added to it to generate the
> next key and the last number is writted to back to the table.  So this table
> only contains one value.  That of the last article added.
>
> Also the problem is that I already have a database that contains articles
> that I need that I am going to move to the new table.
>
> Abe.
> ----- Original Message -----
> From: "John McKown" <joarmc@swbell.net>
> To: "Abe Asghar" <abe@fish.tm>
> Cc: <pgsql-general@postgresql.org>
> Sent: Friday, September 22, 2000 4:11 PM
> Subject: Re: [GENERAL] one more word about rules
>
>
> > Abe,
> > How do you generate your article number? If you are using a SERIAL, then
> > you could change it to use a specific SEQUENCE and step the SEQUENCE by
> > some value other than one. Something like:
> >
> > CREATE SEQUENCE article_sequence INCREMENT 100 MINVALUE 1 START 101;
> >
> > CREATE TABLE article (
> > article_number int4 default nextval('article_sequence')
> > );
> >
> > That would automatically generate article numbers 101, 201, 301, ...
> > thus leaving room for "inserted" articles.
> >
> > On Fri, 22 Sep 2000, Abe Asghar wrote:
> >
> > > Hi everyone,
> > >
> > > I have built a database that uses int4 as the unique identifier for a
> news
> > > database.
> > >
> > > Therefore an article has a identifier 1, the next one has 2 etc.
> > >
> > > Then I order them when they are displayed on the web reversely so that
> the
> > > last article added is at the top of the list.
> > >
> > > I now face a major problem.  If we need to back dackdate an article - I
> > > can't.  This is because the all the indexes are taken up ie 1, 2,
> 3......75
> > > odd records.  If I want to add one between 50 and 51 ie 50.5, I cannot
> > > because the field is an int4.
> > >
> > > One idea I had to get around this was to create a new table with this
> column
> > > as a float and read and write all therecords in with a PHP script.
> > >
> > > Is there an easier way such as converting the column data type from a
> int4
> > > to a float.
> > >
> > > Thanks in advance.
> > > Abe.
> > >
> >
>



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