Thread: [MASSMAIL]Trigger

[MASSMAIL]Trigger

From
Rajesh Kumar
Date:
I have one table with lot of columns (all vehicle details) and also have updated_at column. Everytime there is a change in data, I want to backup the original data into a new table?

What's the best option? A function and trigger before update?

Re: Trigger

From
Thiemo Kellner
Date:

Am 03.04.2024 um 12:30 schrieb Rajesh Kumar:
> I have one table with lot of columns (all vehicle details) and also have 
> updated_at column. Everytime there is a change in data, I want to backup 
> the original data into a new table?
> 
> What's the best option? A function and trigger before update?

I would say so.



Re: Trigger

From
Erik Wienhold
Date:
On 2024-04-03 16:42 +0200, Thiemo Kellner wrote:
> Am 03.04.2024 um 12:30 schrieb Rajesh Kumar:
> > I have one table with lot of columns (all vehicle details) and also have
> > updated_at column. Everytime there is a change in data, I want to backup
> > the original data into a new table?
> > 
> > What's the best option? A function and trigger before update?
> 
> I would say so.

An AFTER trigger is better suited for that because it runs after
constraints are checked and the UPDATE has completed.  This avoids
unnecessary inserts into the audit table in case the UPDATE fails.

The docs have examples on table auditing[1].

[1] https://www.postgresql.org/docs/current/plpgsql-trigger.html#PLPGSQL-TRIGGER-AUDIT-EXAMPLE

-- 
Erik