Re: Need help with trigger
On 23-01-2021 23:29, Melvin Davidson wrote: Maybe this example will help. From https://www.postgresql.org/docs/current/sql-insert.html INSERT INTO distributors AS d (did, dname) VALUES (8, 'Anvil Distribution') ON CONFLICT (did) DO UPDATE SET dname = EXCLUDED.dname || ' (formerly ' || d.dname || ')' WHERE d.zipcode <> '21201'; On Sat, Jan 23, 2021 at 3:47 PM Adrian Klaver wrote: On 1/23/21 12:14 PM, Condor wrote: On 23-01-2021 20:49, Adrian Klaver wrote: On 1/23/21 10:20 AM, Condor wrote: Sorry, I'm sorry, I don't understand something. You mean to do pure INSERT ON CONFLICT DO or to modify the trigger ? No I meant that in the external program you use to fetch the data from the other table and reorganize the fields. Do your test there and do either the INSERT or UPDATE. -- Adrian Klaver adrian.kla...@aklaver.com -- Melvin Davidson Maj. Database & Exploration Specialist Universe Exploration Command – UXC Employment by invitation only! Thanks for the ideas, after sleeping with the thought, on the morning I decided to remove the trigger and do it with a simple function. CREATE OR REPLACE FUNCTION public.log_last_chaged(contractid TEXT, service INTEGER, endd DATE) RETURNS INTEGER LANGUAGE plpgsql AS $function$ DECLARE enddate DATE; BEGIN SELECT INTO enddate end_date FROM arhive_table WHERE contract = contractid AND servid = service AND command = 1; IF enddate IS NULL THEN INSERT INTO arhive_table (contract, serviceid, end_date) VALUES (contractid, service, endd); ELSIF enddate IS DISTINCT FROM endd THEN UPDATE arhive_table SET sendit = 0, end_date = endd, lastseen = CURRENT_TIMESTAMP WHERE contract = contractid AND serviceid = service AND command = 1; ELSE UPDATE arhive_table SET lastseen = CURRENT_TIMESTAMP WHERE contract = contractid AND serviceid = service AND command = 1; END IF; RETURN 1; END; $function$; Thanks again for ideas. HS
Re: Need help with trigger
Maybe this example will help. >From https://www.postgresql.org/docs/current/sql-insert.html INSERT INTO distributors AS d (did, dname) VALUES (8, 'Anvil Distribution') ON CONFLICT (did) DO UPDATE SET dname = EXCLUDED.dname || ' (formerly ' || d.dname || ')' WHERE d.zipcode <> '21201'; On Sat, Jan 23, 2021 at 3:47 PM Adrian Klaver wrote: > On 1/23/21 12:14 PM, Condor wrote: > > On 23-01-2021 20:49, Adrian Klaver wrote: > >> On 1/23/21 10:20 AM, Condor wrote: > > > > > Sorry, > > > > I'm sorry, I don't understand something. You mean to do pure INSERT ON > > CONFLICT DO or to modify the trigger ? > > No I meant that in the external program you use to fetch the data from > the other table and reorganize the fields. Do your test there and do > either the INSERT or UPDATE. > > > -- > Adrian Klaver > adrian.kla...@aklaver.com > > > -- *Melvin Davidson* *Maj. Database & Exploration Specialist* *Universe Exploration Command – UXC* Employment by invitation only!
Re: Need help with trigger
On 1/23/21 12:14 PM, Condor wrote: On 23-01-2021 20:49, Adrian Klaver wrote: On 1/23/21 10:20 AM, Condor wrote: Sorry, I'm sorry, I don't understand something. You mean to do pure INSERT ON CONFLICT DO or to modify the trigger ? No I meant that in the external program you use to fetch the data from the other table and reorganize the fields. Do your test there and do either the INSERT or UPDATE. -- Adrian Klaver adrian.kla...@aklaver.com
Re: Need help with trigger
On 23-01-2021 20:49, Adrian Klaver wrote:
On 1/23/21 10:20 AM, Condor wrote:
On 23-01-2021 18:31, Adrian Klaver wrote:
On 1/23/21 4:57 AM, Condor wrote:
So do an UPDATE and the RETURN NULL to cancel the INSERT. Untested
example:
UPDATE arhive_table SET sendto = 0, uts = date_part('epoch',
CURRENT_TIMESTAMP)::integer WHERE contract = NEW.contract AND service
= NEW.service;
RETURN NULL;
Yep, I think about this update and was my first approach but need to
be done only if end_date is different.
If end_date is the same this mean contract still exists so only update
lastseen column, if the lastseen is not updated other process will
read not seen contracts and will generate report and send them to
delete services. If lastseen is changed and sendto is zero again, mean
end_date is changed and need to be send new end_date again to other
systems.
So add an:
ELSIF enddate = FROM NEW.end_date THEN
and do UPDATE of lastseen column.
Honestly I think this better handled by the external program that
doing the transformation.
Sorry,
I'm sorry, I don't understand something. You mean to do pure INSERT ON
CONFLICT DO or to modify the trigger ?
Re: Need help with trigger
On 1/23/21 10:20 AM, Condor wrote:
On 23-01-2021 18:31, Adrian Klaver wrote:
On 1/23/21 4:57 AM, Condor wrote:
So do an UPDATE and the RETURN NULL to cancel the INSERT. Untested
example:
UPDATE arhive_table SET sendto = 0, uts = date_part('epoch',
CURRENT_TIMESTAMP)::integer WHERE contract = NEW.contract AND service
= NEW.service;
RETURN NULL;
Yep, I think about this update and was my first approach but need to be
done only if end_date is different.
If end_date is the same this mean contract still exists so only update
lastseen column, if the lastseen is not updated other process will read
not seen contracts and will generate report and send them to delete
services. If lastseen is changed and sendto is zero again, mean end_date
is changed and need to be send new end_date again to other systems.
So add an:
ELSIF enddate = FROM NEW.end_date THEN
and do UPDATE of lastseen column.
Honestly I think this better handled by the external program that doing
the transformation.
--
Adrian Klaver
adrian.kla...@aklaver.com
Re: Need help with trigger
On 23-01-2021 18:31, Adrian Klaver wrote:
On 1/23/21 4:57 AM, Condor wrote:
Hello ppl,
I need help with trigger how to replace insert command with update.
External program read data from one table and in every 30 min I need
to refresh data in arhive table.
What is the table being read from and is it in the same database?
Data is read from another table in the same database but is not in the
same format.
See more comments inline below.
What I want is: if data already inserted and end_date is not changed,
only to update lastseen column. If data not exists to insert data and
if data exists and end_date is changed
to update end_date, lastseen and sendto columns. Well, update probably
will never happened, this functionality is left for frontend but its
can be cut off.
and my trigger is:
CREATE OR REPLACE FUNCTION public.log_last_chaged()
RETURNS trigger
LANGUAGE plpgsql
AS $function$
enddate DATE;
BEGIN
IF TG_OP = 'INSERT' THEN
SELECT INTO enddate end_date FROM arhive_table WHERE contract =
NEW.contract AND service = NEW.service;
IF enddate IS NULL THEN
-- line below probably will do normal INSERT
RETURN NEW;
ELSIF enddate IS DISTINCT FROM NEW.end_date THEN
NEW.sendto := 0;
NEW.uts := date_part('epoch', CURRENT_TIMESTAMP)::integer;
-- But here need to do UPDATE not INSERT
So do an UPDATE and the RETURN NULL to cancel the INSERT. Untested
example:
UPDATE arhive_table SET sendto = 0, uts = date_part('epoch',
CURRENT_TIMESTAMP)::integer WHERE contract = NEW.contract AND service
= NEW.service;
RETURN NULL;
Yep, I think about this update and was my first approach but need to be
done only if end_date is different.
If end_date is the same this mean contract still exists so only update
lastseen column, if the lastseen is not updated other process will read
not seen contracts and will generate report and send them to delete
services. If lastseen is changed and sendto is zero again, mean end_date
is changed and need to be send new end_date again to other systems.
END IF;
ELSIF TG_OP = 'UPDATE' THEN
IF OLD.end_date IS DISTINCT FROM NEW.end_date THEN
NEW.sendto := 0;
NEW.uts := date_part('epoch', CURRENT_TIMESTAMP)::integer;
END IF;
END IF;
-- lastseen must always be updated with CURRENT_TIMESTAMP if
contract is seen
NEW.lastseen := CURRENT_TIMESTAMP;
RETURN NEW;
END
$function$;
DROP TRIGGER IF EXISTS last_changes ON arhive_table;
CREATE TRIGGER last_changes
BEFORE INSERT OR UPDATE OF end_date ON arhive_table
FOR EACH ROW
WHEN (pg_trigger_depth() < 1)
EXECUTE FUNCTION log_last_chaged();
Regards,
HS
Re: Need help with trigger
On 23-01-2021 18:17, David G. Johnston wrote: On Saturday, January 23, 2021, Condor wrote: Hello ppl, I need help with trigger how to replace insert command with update. External program read data from one table and in every 30 min I need to refresh data in arhive table. What I want is: if data already inserted and end_date is not changed, only to update lastseen column. If data not exists to insert data and if data exists and end_date is changed to update end_date, lastseen and sendto columns. Well, update probably will never happened, this functionality is left for frontend but its can be cut off. Seems like an insert on conflict would be simpler. Otherwise, what is your question or concern? David J. This was my first approach, but as the sample data I provide, end_date will always be updated not only if it is changed and my goal is to have no meaningless records. My question is there a way to update the trigger instead of inserting. HS
Re: Need help with trigger
On 1/23/21 4:57 AM, Condor wrote:
Hello ppl,
I need help with trigger how to replace insert command with update.
External program read data from one table and in every 30 min I need to
refresh data in arhive table.
What is the table being read from and is it in the same database?
See more comments inline below.
What I want is: if data already inserted and end_date is not changed,
only to update lastseen column. If data not exists to insert data and if
data exists and end_date is changed
to update end_date, lastseen and sendto columns. Well, update probably
will never happened, this functionality is left for frontend but its can
be cut off.
and my trigger is:
CREATE OR REPLACE FUNCTION public.log_last_chaged()
RETURNS trigger
LANGUAGE plpgsql
AS $function$
enddate DATE;
BEGIN
IF TG_OP = 'INSERT' THEN
SELECT INTO enddate end_date FROM arhive_table WHERE contract =
NEW.contract AND service = NEW.service;
IF enddate IS NULL THEN
-- line below probably will do normal INSERT
RETURN NEW;
ELSIF enddate IS DISTINCT FROM NEW.end_date THEN
NEW.sendto := 0;
NEW.uts := date_part('epoch', CURRENT_TIMESTAMP)::integer;
-- But here need to do UPDATE not INSERT
So do an UPDATE and the RETURN NULL to cancel the INSERT. Untested example:
UPDATE arhive_table SET sendto = 0, uts = date_part('epoch',
CURRENT_TIMESTAMP)::integer WHERE contract = NEW.contract AND service =
NEW.service;
RETURN NULL;
END IF;
ELSIF TG_OP = 'UPDATE' THEN
IF OLD.end_date IS DISTINCT FROM NEW.end_date THEN
NEW.sendto := 0;
NEW.uts := date_part('epoch', CURRENT_TIMESTAMP)::integer;
END IF;
END IF;
-- lastseen must always be updated with CURRENT_TIMESTAMP if contract
is seen
NEW.lastseen := CURRENT_TIMESTAMP;
RETURN NEW;
END
$function$;
DROP TRIGGER IF EXISTS last_changes ON arhive_table;
CREATE TRIGGER last_changes
BEFORE INSERT OR UPDATE OF end_date ON arhive_table
FOR EACH ROW
WHEN (pg_trigger_depth() < 1)
EXECUTE FUNCTION log_last_chaged();
Regards,
HS
--
Adrian Klaver
adrian.kla...@aklaver.com
Re: Need help with trigger
On Saturday, January 23, 2021, Condor wrote: > > > Hello ppl, > > I need help with trigger how to replace insert command with update. > External program read data from one table and in every 30 min I need to > refresh data in arhive table. > What I want is: if data already inserted and end_date is not changed, only > to update lastseen column. If data not exists to insert data and if data > exists and end_date is changed > to update end_date, lastseen and sendto columns. Well, update probably > will never happened, this functionality is left for frontend but its can be > cut off. > Seems like an insert on conflict would be simpler. Otherwise, what is your question or concern? David J.
