I want to store the result of the following loop in a table:
DO $$
DECLARE rec RECORD;
BEGIN
FOR rec IN SELECT c1 FROM t1
LOOP
SELECT foo(rec.c1);
END LOOP;
END; $$
LANGUAGE 'plpgsql';
How can I do that?
You don't need a loop for that at all. In fact you don't even need a function for that:
insert into some_table (some_column)
select foo(c1)
from t1
Or if you want to create the table based on the query:
create table_some
as
select foo(c1) as some_column
from t1;
Related
In Postgres, someone knows how to substitute the value of the variable in a NEW.variable in a trigger?
For instance, I have a variable with value order_code. I want to execute NEW.variable so that it's getting in fact NEW.order_code.
In detailed:
I have a function to obtain the primary key column of a table:
CREATE FUNCTION getPrimaryKey(_table_name VARCHAR(50))
RETURNS SETOF VARCHAR(50) AS $$
DECLARE
primary_key VARCHAR(50);
BEGIN
FOR primary_key IN SELECT a.attname
FROM pg_index i
JOIN pg_attribute a ON a.attrelid = i.indrelid
AND a.attnum = ANY(i.indkey)
WHERE i.indrelid = _table_name::regclass
AND i.indisprimary LOOP
RETURN NEXT primary_key;
END LOOP;
END;
$$ LANGUAGE plpgsql;
Then I have a trigger to collect some info when an INSERT is done in a table. The procedure in the trigger is called from several triggers from different tables. That's why it's so generic and I have this need.
What I want is to obtain the primary key of the object inserted.
CREATE FUNCTION logAudit()
RETURNS trigger AS $$
DECLARE primary_key VARCHAR(50);
BEGIN
primary_key := getprimarykey(TG_TABLE_NAME::VARCHAR(50));
INSERT INTO test VALUES (TG_TABLE_NAME);
INSERT INTO test VALUES (NEW.primary_key);
RETURN NULL;
END;
$$ LANGUAGE plpgsql;
CREATE TRIGGER audit_in_client
AFTER INSERT ON tb_client
FOR EACH STATEMENT EXECUTE PROCEDURE logAudit();
The NEW.primary_key is what is causing me issues. I expect primary_key to be the column name of the source table where the insert happened. What I want in NEW.primary_key is to actually use the value in the variable.
Here is the example of anonymous pl/pgsql block which doing something what you want:
do $$
declare
v pg_database = (pg_database) from pg_database where datname = 'template1';
fname text = 'datname';
n text;
begin
n := to_jsonb(v)->>fname;
raise info '%', n;
end $$;
Output:
INFO: template1
It is working example. In your trigger function it could be something like
declare
pk_name text;
pk_value text;
begin
pk_name := getprimarykey(TG_TABLE_NAME::VARCHAR(50));
pk_value := to_jsonb(NEW) ->> pk_name;
-- Do what you want with pk_value here
return null;
end $$;
I'm trying to get a customer id which can be placed in one of ten different tables. I don't want to hard code those table names to find it so I tried postgresql function as follows.
create or replace FUNCTION test() RETURNS SETOF RECORD AS $$
DECLARE
rec record;
BEGIN
select id from schema.table_0201_0228 limit 1 into rec;
return next rec;
select id from schema.table_0301_0331 limit 1 into rec;
return next rec;
END $$ language plpgsql;
select * from test() as (id int)
As I'm not familiar with postgresql function usage, how can I improve the code to replace 'schema.table1' with a variable, loop each table and return the result?
NOTE: table names may change overtime. For example, table_0201_0228 and table_0301_0331 are for February and March respectively.
You need dynamic SQL for that:
create or replace FUNCTION test(p_schema text)
RETURNS table(id int)
AS $$
DECLARE
l_tab record;
l_sql text;
BEGIN
for l_tab in (select schemaname, tablename
from pg_tables
where schemaname = p_schema)
loop
l_sql := format('select id from %I.%I limit 1', l_tab.schemaname, l_tab.tablename);
return query execute l_sql;
end loop;
END $$
language plpgsql;
I made the schema name a parameter, but of course you can hard-code it. As the function is defined as returns table there is no need to specify the column name when using it:
select *
from test('some_schema');
I have problem when create function for trigger. I want to UPDATE inserted value BEFORE INSERT data to DB.
My code look like this:
CREATE OR REPLACE FUNCTION test_func()
RETURNS TRIGGER AS
$$
DECLARE cnt INTEGER;
BEGIN
cnt := COUNT(*) FROM sample_tbl WHERE id = NEW.id AND created_date = NEW.created_date;
NEW.current_order := cnt + 1; // I want to set value of sample_tbl.current_order automatically
END
$$ LANGUAGE plpgsql;
CREATE TRIGGER test_trigger
BEFORE INSERT
ON test_tbl
FOR EACH ROW
EXECUTE PROCEDURE test_func();
I inserted data then IDE said:
control reached end of trigger procedure without RETURN
Where: PL/pgSQL function test_func()
The error says that you must return something from the Trigger ( either NEW or NULL )
There's no Trigger needed for this. A simple View using this select query will give you the required result
--create or replace view sample_view as
select t.id, t.created_date,
row_number() OVER ( partition by id,created_date order by id ) as current_order
FROM sample_tbl t;
This will exactly match the records if updated using a Trigger
CREATE OR REPLACE FUNCTION test_func()
RETURNS TRIGGER AS
$$
DECLARE cnt INTEGER;
BEGIN
select COUNT(*) INTO cnt FROM sample_tbl WHERE id = NEW.id
AND created_date = NEW.created_date;
NEW.current_order := cnt + 1;
RETURN NEW; --required
END
$$ LANGUAGE plpgsql;
Demo
Your trigger function is just missing RETURN NEW; statement:
CREATE OR REPLACE FUNCTION test_func()
RETURNS TRIGGER AS
$$
DECLARE cnt INTEGER;
BEGIN
cnt := COUNT(*) FROM sample_tbl WHERE id = NEW.id AND created_date = NEW.created_date;
NEW.current_order := cnt + 1;
RETURN NEW;
END
$$ LANGUAGE plpgsql;
Hi I have a Registra_cambios () function; which want to assign to all tables in my database, I wonder if you can concatenate the trigger name with the record (table name) my cursor to not have the same trigger name on all tables
create trigger example t_log_ "record" ()
CREATE OR REPLACE FUNCTION ActiveTriggers() returns void as $$
DECLARE
r record;
c CURSOR FOR SELECT table_name as tab FROM information_schema.tables WHERE table_schema='public' AND table_type='BASE TABLE';
BEGIN
FOR r IN c LOOP
create trigger t_log_r before insert or update or delete
on r.tab
for each row
execute procedure Registra_cambios();
END LOOP;
END;
$$ LANGUAGE plpgsql;
soemthing like?..
do
$$
declare
r record;
begin
for r in (SELECT table_name as tab FROM information_schema.tables WHERE table_schema='public' AND table_type='BASE TABLE';) loop
execute 'create trigger t_log_r_'||r.tab||' before insert or update or delete
on '||r.tab||'
for each row
execute procedure Registra_cambios()';
end loop;
end;
$$
;
CREATE FUNCTION cs_refresh_mviews() RETURNS integer AS $$
DECLARE
mviews RECORD;
BEGIN
PERFORM cs_log('Refreshing materialized views...');
FOR mviews IN SELECT * FROM cs_materialized_views ORDER BY sort_key LOOP
-- How For columns of mviews?
END LOOP;
PERFORM cs_log('Done refreshing materialized views.');
RETURN 1;
END;
$$ LANGUAGE plpgsql;
I want get value of columns in mviews.
How browser columns of mviews use to For or While?
The same as:
For i=0 to mviews.columns.count step i++
raise mviews[i]
Materialized Views, really? Are you on 9.3 already?
Anyways your question is not very clear, are you trying to iterate for all the columns in each view?
The Information Schema and information_schema.columns in particular can be what you are looking for.
Assuming you have some schema and name fields in cs_materialized_views table, you can do something like that:
Declare another Record variable: mcols RECORD;
And put this inside your loop:
FOR mcols IN (SELECT ordinal_position, column_name FROM information_schema.columns WHERE table_schema = mviews.schema AND table_name = mviews.name ORDER BY ordinal_position) LOOP
RAISE NOTICE 'View %, Column no. %: %', mviews.table_name, mcols.ordinal_position, mcols.column_name;
END LOOP;