Re: Having more than one constraint trigger on a table

On 10/22/19 8:26 AM, Andreas Joseph Krogh wrote:
> På tirsdag 22. oktober 2019 kl. 17:12:59, skrev Adrian Klaver
> <adrian(dot)klaver(at)aklaver(dot)com <mailto:adrian(dot)klaver(at)aklaver(dot)com>>:
>
> [snip]
> No.
> When I sort the triggers I get:
>
> test=# create table trg_str(fld_1 varchar);
> CREATE TABLE
> test=# insert into trg_str values ('trigger_1_update_fts'),
> ('trigger_2'), ('trigger_3'), ('trigger_1_check_nocycle');
> INSERT 0 4
> test=# select * from trg_test order by fld_1 ;
>   id | fld_1
> ----+-------
> (0 rows)
>
> test=# select * from trg_str order by fld_1 ;
>            fld_1
> -------------------------
>   trigger_1_check_nocycle
>   trigger_1_update_fts
>   trigger_2
>   trigger_3
>
> Is this how you want them to fire as it does not match what you say
> above?:
>
> (I know they were not /declared/ in that order, but..)
> Yes, all "trigger_1_*" are the "actuall triggers triggering the logic",
> trigger_2 and trigger_3 are only there as part of the "make
> constraint-triggers fire only once"-mechanism, in which the function in
> the first trigger is the function performing the actual logic.
> So, being I want 2 "logical chunks" to happen I have two
> "trigger_1"-triggers (there is no established terminilogy for this
> AFAIK), each calling a function performing the logick which is to happen
> only once (per row).
>
> "The first "main" trigger-function is update_company_fts_tf() ... The
> second "main" trigger-function is company_parent_no_cycle()"
>
> It might be easier to understand if sketch out a schematic version of
> what you are trying to achieve.
>
> The point is; I want to functions to be called
> - update_company_fts_tf()
> - company_parent_no_cycle()
> , each only once, as constraint-triggers on the same table. So they are
> called by the "level 1 triggers" which must fire first.

To be clear the order they fire relative to each other is not important?

> Is it clearer now what I'm trying to achieve?

Sort of, though I am still not entirely what the whole process is trying
to achieve. What the mix of deferred and un-deferred triggers and
'logical' and housekeeping functions are doing is not clear to me. That
is why I suggested a schematic representation of the trigger flow would
be helpful. Leave out the fine details and create a flow chart of what
you want to happen.

> --
> Andreas Joseph Krogh

--
Adrian Klaver
adrian(dot)klaver(at)aklaver(dot)com