I have a table with event entity
create table event_entity
(
id varchar(36) not null
constraint constraint_4
primary key,
details_json varchar(2550),
event_time bigint,
type varchar(255),
user_id varchar(255)
);
details_json has such data:
{
"custom_required_action":"VERIFY_EMAIL",
}
I need to create a trigger and notify on inserted row event_entity table with condition:
WHERE type = 'CUSTOM_REQUIRED_ACTION' AND details_json:custom_required_action = 'VERIFY_EMAIL'
I've made it with
CREATE OR REPLACE FUNCTION notify_verifyEmail()
RETURNS trigger AS $$
DECLARE
BEGIN
PERFORM pg_notify(
'verifyEmail',
row_to_json(NEW)::text);
RETURN NEW;
END;
$$ LANGUAGE plpgsql;
CREATE TRIGGER notify_verifyEmail
AFTER INSERT ON event_entity
FOR EACH ROW
WHEN (new.type = 'CUSTOM_REQUIRED_ACTION')
EXECUTE PROCEDURE notify_verifyEmail();
But how to add second condition with details_json field?
First create the notification trigger function. In the example below it will notify on the_notification_channel and have the new row values JSON formatted as notification payload. The names of the trigger, the trigger function and the notification channel are such for illustration only.
create or replace function the_notification_trigger_function()
returns trigger language plpgsql as
$$
begin
perform pg_notify('the_notification_channel', to_json(new)::text);
return null;
end;
$$;
and then create the trigger with a condition
create trigger the_notification_trigger
after insert on event_entity for each row
when new.type = 'CUSTOM_REQUIRED_ACTION'
and new.details_json::json ->> 'custom_required_action' = 'VERIFY_EMAIL'
execute function the_notification_trigger_function();
Unrelated but it would be much better if your details_json field was of type jsonb instead of text and event_time was of type timestamp instead of bigint. What is constraint_4?
It might be a good idea to move the new.details_json::json ->> 'custom_required_action' = 'VERIFY_EMAIL' sub-condition into the trigger function so that the trigger fill fire on every 'CUSTOM_REQUIRED_ACTION' and the function would decide on how to react.
can u try with below once and let me if it works
CREATE TRIGGER notify_verifyEmail
AFTER INSERT ON event_entity
FOR EACH ROW
WHEN (new.type = 'CUSTOM_REQUIRED_ACTION' AND (new.details_json->>'custom_required_action') = 'VERIFY_EMAIL')
EXECUTE PROCEDURE notify_verifyEmail();
Related
here is my script:
CREATE SCHEMA IF NOT EXISTS {accountId};
CREATE TABLE IF NOT EXISTS {accountId}.{tableCommandsName}
(
id int GENERATED ALWAYS AS IDENTITY,
ts timestamp WITHOUT TIME ZONE NOT NULL,
command varchar NOT NULL,
ts_executed timestamp WITHOUT TIME ZONE,
output varchar
);
CREATE INDEX IF NOT EXISTS idx_commands ON {accountId}.{tableCommandsName} (ts_executed) WHERE ts_executed IS NULL;
CREATE OR REPLACE VIEW {accountId}.pending_commands AS
SELECT id, ts, command from {accountId}.{tableCommandsName} WHERE ts_executed IS NULL ORDER BY ts ASC;
CREATE OR REPLACE FUNCTION {accountId}.on_commands_change ()
RETURNS trigger
LANGUAGE 'plpgsql'
AS $BODY$
DECLARE
notification JSON;
BEGIN
notification = json_build_object(
'table',TG_TABLE_NAME,
'data', row_to_json(NEW));
PERFORM pg_notify('datachange', notification::TEXT);
RETURN NEW;
END
$BODY$;
CREATE OR REPLACE TRIGGER {triggerName}
AFTER INSERT ON {accountId}.{tableCommandsName}
FOR EACH ROW EXECUTE PROCEDURE {accountId}.on_commands_change();
my focus is the line:
CREATE OR REPLACE TRIGGER {triggerName}
where
CREATE OR REPLACE TRIGGER {accountId}.{triggerName}
will not work, but
CREATE OR REPLACE TRIGGER "{accountId}.{triggerName}"
will work, and I don't understand why.
everything else has the schema name in front, but the trigger doesn't want it.
and if I don't put it, it's still created in the right schema. Is it because it's during the same execution as the create schema instruction?
Quote from the manual
The name cannot be schema-qualified — the trigger inherits the schema of its table
I have a really simple problem and I am probably overthinking this way too much. But here it goes:
I want the fields of a column in one of my tables to be filled automatically whenever I make a new record. The value should be the same (UUID) as the specified (UUID) value from a column in another table. These two columns are joined via a foreign key. So far I have tried making a trigger function but with no results so far:
Create or replace function project_id()
returns trigger
as $$ begin
if new.project_id is null then
insert into sporen (project_id)
select project_id
from project_info
where project_code = 'ant0001';
end if;
return new;
end;
$$ language plpgsql;
CREATE TRIGGER
project_id_default
BEFORE update ON
sporen
FOR EACH ROW EXECUTE PROCEDURE project_id();
Do I need to specify something as a default in my table? Or am I going about it completely wrong?
You only need to assign project_info.project_id to NEW.project_id in your trigger function. No INSERT is needed. Here is an illustration.
Create or replace function project_id() returns trigger as
$$
begin
if new.project_id is null then
new.project_id :=
(
select pi.project_id
from project_info pi
where pi.project_code = NEW.project_code
);
end if;
return new;
end;
$$ language plpgsql;
You do not need to specify a default value for project_id in your table.
I used this example and it worked well when all my tables were in public schema.
But trigger hasn't been working since I separated tables into different schemas and applied inheriting.
Here is example of my structure:
CREATE SCHEMA common;
CREATE SCHEMA video;
CREATE TABLE common.file (
file_id SERIAL PRIMARY KEY,
url VARCHAR(255) NOT NULL,
mime_type VARCHAR(31) DEFAULT '' NOT NULL,
size INTEGER NOT NULL,
modified TIMESTAMP DEFAULT CURRENT_TIMESTAMP NOT NULL
);
CREATE TABLE video.file (
width INTEGER NOT NULL,
height INTEGER NOT NULL,
local_path VARCHAR(255) DEFAULT '' NOT NULL
)
INHERITS (common.file);
CREATE FUNCTION common.update_modified()
RETURNS trigger
LANGUAGE plpgsql
AS $$
BEGIN
NEW.modified = now();
RETURN NEW;
END;
CREATE TRIGGER update_modified
BEFORE UPDATE ON common.file
FOR EACH ROW EXECUTE PROCEDURE common.update_modified();
When I do UPDATE common.file ... or UPDATE video.file ... field common.file.modified doesn't change itself. It seems trigger doesn't run, but I don't understand why.
What should I do to repair the behavior?
In described issue trigger is set only on common.file, so UPDATE common.file ... doesn't work if row inserted in video.file
Documentation says: INSERT always inserts into exactly the table specified
So trigger should be applied to both common.file and video.file.
-- Creating schemas and tables the same
-- Let function be in public scheme
CREATE FUNCTION update_modified()
RETURNS trigger
LANGUAGE plpgsql
AS $$
BEGIN
NEW.modified = now();
RETURN NEW;
END;
CREATE TRIGGER update_modified
BEFORE UPDATE ON common.file
FOR EACH ROW EXECUTE PROCEDURE update_modified();
CREATE TRIGGER update_modified
BEFORE UPDATE ON video.file
FOR EACH ROW EXECUTE PROCEDURE update_modified();
In that case when we update rows inserted either in common.file or in video.file corresponding trigger will call.
Here is my sample table.
CREATE TABLE employee_test(
idTst SERIAL PRIMARY KEY,
monthDownload VARCHAR(6),
changeDate DATE);
I am trying to create a function and trigger that would update changeDate attribute with a current date when monthDownload attribute is updated.
The function I have it works with one problem. It updates all records instead of the one that was updated.
CREATE OR REPLACE FUNCTION downloadMonthChange()
RETURNS TRIGGER AS
$$
BEGIN
IF NEW.monthDownload <> OLD.monthDownload THEN
UPDATE employee_test
SET changeDate = current_date
where OLD.idTst = NEW.idTst;
END IF;
RETURN NEW;
END;
$$
Language plpgsql;
Trigger
Create TRIGGER dataTest
AFTER UPDATE
ON employee_test
FOR EACH ROW
EXECUTE PROCEDURE downloadMonthChange();
When I execute the following Update statement:
UPDATE employee_test SET monthDownload = 'oct12'
WHERE idTst = 1;
All changeDate rows get update with a current date.
Is there a way to have only a row with changed record to have a current date updated.
If you use a before trigger you can write directly to NEW
CREATE OR REPLACE FUNCTION downloadMonthChange()
RETURNS TRIGGER AS
$$
BEGIN
IF NEW.monthDownload <> OLD.monthDownload THEN
NEW.changeDate = current_date;
END IF;
RETURN NEW;
END;
$$
Language plpgsql;
the other option when you must use an after trigger is to include the primary key in the where clause. It appears that you were trying to do this, but you had a spurious OLD in the query. beause of that the where clause was only looking at the record responsible for the trigger call, and not limiting which records were to be updated.
IF NEW.monthDownload <> OLD.monthDownload THEN
UPDATE employee_test
SET changeDate = current_date
where idTst = NEW.idTst;
Is it possible to dynamically change column values in NEW with a Trigger Function?
Triggers:
CREATE TRIGGER lowercase_username_on_insert_trigger BEFORE INSERT OR UPDATE ON users
FOR EACH ROW EXECUTE PROCEDURE lowercase_on_insert('username');
CREATE TRIGGER lowercase_email_on_insert_trigger BEFORE INSERT OR UPDATE ON users
FOR EACH ROW EXECUTE PROCEDURE lowercase_on_insert('email');
Trigger Function:
CREATE OR REPLACE FUNCTION lowercase_on_insert()
RETURNS trigger
AS $lowercase_on_insert$
BEGIN
-- e.g., NEW.username = LOWER(NEW.username)
-- -OR- NEW.email = LOWER(NEW.email)
EXECUTE FORMAT('NEW.%s = LOWER(NEW.%s);', TG_ARGV[0], TG_ARGV[0]);
RETURN NEW;
END
$lowercase_on_insert$ LANGUAGE plpgsql;
I get an ERROR: syntax error at or new "NEW" whenever I run an INSERT.
This is my table:
CREATE TABLE users (
id BIGSERIAL PRIMARY KEY,
username VARCHAR(55) NOT NULL UNIQUE,
email VARCHAR(120) NOT NULL UNIQUE
);
Change your Trigger function as below
CREATE OR REPLACE FUNCTION lowercase() RETURNS trigger AS $$
BEGIN
NEW.username = LOWER(NEW.username);
NEW.email = LOWER(NEW.email);
RETURN NEW;
END;
$$ LANGUAGE plpgsql;
and assign
CREATE TRIGGER tgrr BEFORE INSERT OR UPDATE ON users
FOR EACH ROW EXECUTE PROCEDURE lowercase();
OR
You can directly apply lower() function in Insert/Update like this
insert into users(username,email) values (lower('Jerry'),lower('JeRRY#mail.COM'));
update users set username=lower('JERRY'),email=lower('JERRY#MAIL.COM') where id =1