Re: Can I do this?

From: Michael Nolan <htfoot(at)gmail(dot)com>
To: stan <stanb(at)panix(dot)com>
Cc: pgsql-general(at)lists(dot)postgresql(dot)org
Subject: Re: Can I do this?
Date: 2020-01-16 15:39:59
Message-ID: CAOzAquKmW1jw11nQH7_sd+F5PWRZFLW5kSaHUHMNoMABjb_Z0Q@mail.gmail.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-general

On Thu, Jan 16, 2020 at 6:28 AM stan <stanb(at)panix(dot)com> wrote:

> I am trying to create a function to automatically create a reference value
> when a record is inserted into a table. I want the reference value to
> consist of the user that is doing the insert, plus a couple of dates, plus
> a sequence number, where the sequence number will increment every time a
> given user inserts a record. because this sequence number is user specific,
> my first thought is not to use a set of sequences for it, but to do this
> by
> selecting the maximum sequence number that user has entered in the past.
>
> What happens if two transactions by/for the same user are committed at
around the same point in time? The advantage of sequences is they're
guaranteed to be unique, I'm not sure counting the number of previous
records and adding one will always assure that.
--
Mike Nolan

In response to

Responses

Browse pgsql-general by date

  From Date Subject
Next Message Adrian Klaver 2020-01-16 16:17:13 Re: Is there a GoTo ?
Previous Message Justin 2020-01-16 14:49:04 Re: Can I drop a NOT NUL constrain on an existing table?