I am trying to make an insert statement into a table with the following schema
CREATE TABLE auth(
id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
role VARCHAR(64)
);
I am using pgcrypto extension to generate uuids. Is it possible to append id to the role field while inserting a row in this table?
I am inserting in this table using
insert into auth (role) values ('admin');
I want to append the id generated to admin so that the role would look something like admin_12234-3453-3453-345-34534.
You need an insert trigger to do this:
CREATE FUNCTION admin_uuid() RETURNS trigger AS $$
BEGIN
NEW.role := NEW.role || NEW.id::text;
RETURN NEW;
END;
$$ LANGUAGE plpgsql STABLE;
CREATE TRIGGER set_admin_uuid
BEFORE INSERT ON auth
FOR EACH ROW EXECUTE PROCEDURE admin_uuid();
I think there is no direct way to achieve this. But postgres allows defining rules on tables and views (see https://www.postgresql.org/docs/9.2/static/sql-createrule.html). You can create a new rule for insertion which creates the id and the role as desired.
Related
I need to create a trigger in postgres where, when I add a record to table A, it automatically inserts its primary key value (which is auto incremented) into table B, the primary key of table A is the foreign key in table B.
I have tried doing it through pgadmin but it does not allow me to save. Could someone help out please.
First create the following trigger function.
CREATE OR REPLACE FUNCTION auto_insert() RETURNS TRIGGER AS
$BODY$
BEGIN
INSERT INTO
B(a_id)
VALUES(new.id);
RETURN new;
END;
$BODY$
language plpgsql;
And then attach the trigger function to table A.
CREATE TRIGGER auto_inserter
AFTER INSERT ON A
FOR EACH ROW
EXECUTE PROCEDURE auto_insert();
I am using Prisma as my schema and migrating it to supabase with prisma migrate dev
One of my tables Profiles, should reference the auth.users table in supabase, in sql something like this id uuid references auth.users not null,
Now since that table is automatically created in supabase do I still add it to my prisma schema? It's not in public either it is in auth.
model Profiles {
id String #id #db.Uuid
role String
subId String
stripeCustomerId String
refundId String[]
createdAt DateTime #default(now())
updatedAt DateTime #updatedAt
}
The reason I want the relation is because I want a trigger to automatically run a function that inserts an id and role into the profiles table when a new users is invited.
This is that trigger and function
-- inserts a row into public.profiles
create function public.handle_new_user()
returns trigger
language plpgsql
security definer
as $$
begin
insert into public.Profiles (id, role)
values (new.id, 'BASE_USER');
return new;
end;
$$;
-- trigger the function every time a user is created
create trigger on_auth_user_created
after insert on auth.users
for each row execute procedure public.handle_new_user();
I had this working when I created the profiles table manually in supabase I included the reference to the auth.users, that's the only reason I can think of why the user Id and role won't insert into the profiles db when I invite a user, the trigger and function are failing
create table public.Profiles (
id uuid references auth.users not null,
role text,
primary key (id)
);
Update from comment:
One error I found is
relation "public.profiles" does not exist
I change it to "public.Profiles" with a capital in supabase, but the function seem to still be looking for lowercase.
What you show should just work:
db<>fiddle here
Looks like you messed up capitalization with Postgres identifiers.
If you (or your ORM) created the table as "Profiles" (with double-quotes), non-standard capitalization is preserved and you need to double-quote the name for the rest of its life.
So the trigger function body must read:
...
insert into public."Profiles" (id, role) -- with double-quotes
...
Note that schema and table (and column) have to be quoted separately.
See:
Are PostgreSQL column names case-sensitive?
I want to create a sequence for each row created in the table account, like os_1, os_2, etc...
How can I get the id of this new row and insert it on the name of the sequence?
CREATE OR REPLACE FUNCTION public.create_os_seq() RETURNS TRIGGER AS $$
#variable_conflict use_variable
BEGIN
--CREATE SEQUENCE seqname;
EXECUTE format('CREATE SEQUENCE os_', NEW.id);
return NEW;
END;
$$ LANGUAGE plpgsql;
CREATE TRIGGER create_os_seq AFTER INSERT ON account FOR EACH ROW EXECUTE PROCEDURE create_os_seq();
Table account
id INT AUTO_INCREMENT
nane VARCHAR
After creating a sequence i´ll put its number in the OS table
table os
id INT
account_id INT
From your question I assume you want to take care of self incrementing values?.. Postgres uses shortcut SERIAL instead of AUTO_INCREMENT, just create table like:
CREATE TABLE so79 (id bigserial primary key, col text);
That will automatically create sequence for you and assign its value as default for column id. Basically will make it smth like AUTO_INCREMENT. You don't have to use trigger to increment values...
There is no way that creating a sequence for each row is a good idea. Instead, tell us what you're trying to do.
My guess is you need a waterline indicator, a high point you intend to increment on some action. Just use an integer.
CREATE TABLE foo (
foo_id serial,
max_seen int
);
Now you can do whatever with triggers on other tables and such to increment max_seen.
I've two tables accounts and projects:
create table accounts (
id bigserial primary key,
slug text unique
);
create table projects (
id bigserial primary key,
account_id bigint not null references accounts (id),
name text
);
I want to be able to insert a new row into projects by specifying only account.slug (not account.id). What I'm trying to achieve is something like:
INSERT into projects (account_slug, name) values ('account_slug', 'project_name');
I thought about using a trigger (unfortunately it doesn't work):
create or replace function trigger_projects_insert() returns trigger as $$
begin
if TG_OP = 'INSERT' AND NEW.account_slug then
select id as account_id
from accounts as account
where account.slug = NEW.account_slug;
NEW.account_id = account_id;
-- we should also remove NEW.account_slug but don't know how
end if;
return NEW;
end;
$$ LANGUAGE plpgsql;
create trigger trigger_projects_insert before insert on projects
for each row execute procedure trigger_projects_insert();
What is the best way to achieve what I'm trying to do?
Is a trigger a good idea?
Is there any other solution?
WITH newacc AS (
INSERT INTO accounts (slug)
VALUES ('account_slug')
RETURNING id
)
INSERT INTO projects (account_id, name)
SELECT id, 'project_name'
FROM newacct;
If you are limited in the SQL you can use, another idea might be to define a view over both tables and create an INSTEAD OF INSERT trigger on the view that performs the two INSERTs on the underlying tables. Then an INSERT statement like the one in your question would work.
Is it possible to configure a Postgres database such that a specific column may only be updated by a trigger, while still allowing the trigger itself to be executed in response to an update by a role without permission to update that column? If so, how?
For example, given tables and a trigger like this:
CREATE TABLE a(
id serial PRIMARY KEY,
flag boolean NOT NULL DEFAULT TRUE,
data text NOT NULL
);
CREATE TABLE b(
id serial PRIMARY KEY,
updated_on DATE NOT NULL DEFAULT CURRENT_DATE,
a_id INTEGER NOT NULL,
FOREIGN KEY (a_id) references a(id)
);
CREATE FUNCTION update_aflag() RETURNS trigger AS $update_aflag$
BEGIN
UPDATE a
SET flag = FALSE
WHERE id = NEW.a_id;
RETURN NEW;
END;
$update_aflag$ LANGUAGE plpgsql;
CREATE TRIGGER update_aflag_trigger
AFTER INSERT ON b
FOR EACH ROW
EXECUTE PROCEDURE update_aflag()
;
I'd like to define a role which does not have permission to update a.flag directly using an UPDATE statement, but which may update flag indirectly via the trigger.
Yes, this is possible using a SECURITY DEFINER trigger function. The trigger function runs as a role that has the right to modify the flag column, but you don't GRANT that right to normal users. You should create the trigger function as the role that you'll grant the required rights to.
This requires that the application not run as the user that owns the tables, and of course not as a superuser.
You can GRANT column update rights to other columns to the user, just leave out the flag column. Note that GRANTing UPDATE on all columns then REVOKEing it on flag will not work, it's not the same thing.