How to implement execute command inside for loop - postgres, dbeaver - postgresql

Question

I am new to postgres. I need to create a function that will take a list of all the tables in the database whose names are stored in one table and then delete the records of all the tables that are older than x days and have a certain row_status. Some tables do not have a row_status column.
I get an error when I try to save a written function in dbeaver -> ERROR: syntax error at or near "||"
create function delete_old_records1(day1 int, row_status1 character default null, row_status2 character default null)
returns void
language plpgsql
as $$
declare
c all_tables1%rowtype;
begin
for c in select * from all_tables1 loop
if exists(SELECT column_name FROM information_schema.columns
WHERE table_schema = 'yard_kondor' AND table_name =c.table_name AND column_name = 'row_status') then
execute 'delete from '||c.table_name||' where row_create_datetime>current_date-day1+1 and
row_status in (coalesce(row_status1,''P''), row_status2)';
else
execute 'delete from '||c.table_name||' where row_create_datetime>current_date-day1+1';
raise notice 'Table '||c.table_name||' does not have row_status column';
end if;
end loop;
return;
commit;
end;
$$

Answer 1

Your immediate problem is this line:
raise notice 'Table '||c.table_name||' does not have row_status column';
That should be:
raise notice 'Table % does not have row_status column', c.table_name;
However, your function could be improved a bit. In general it is highly recommended to use format() to generate dynamic SQL to properly deal with identifiers. You also can't commit in a function. If you really need that, use a procedure.
create function delete_old_records1(day1 int, row_status1 character default null, row_status2 character default null)
returns void
language plpgsql
as $$
declare
c all_tables1%rowtype;
begin
for c in select * from all_tables1
loop
if exists (SELECT column_name FROM information_schema.columns
WHERE table_schema = 'yard_kondor'
AND table_name = c.table_name
AND column_name = 'row_status') then
execute format('delete from %I
where row_create_datetime > current_date - %J + 1
and row_status in (coalesce(row_status1,%L), row_status2)', c.table_name, day1, 'P');
else
execute format('delete from %I where row_create_datetime > current_date - day1 + 1', c.table_name);
raise notice 'Table % does not have row_status column', c.table_name;
end if;
end loop;
return;
-- you can't commit in a function
end;
$$

Answer 2

Thank you for answer. Now I'm able to save function, but currently I have a problem with running the function.
I started the function with:
DO $$ BEGIN
PERFORM "delete_old_records1"(31,'P','N');
END $$;
I started script with ALT+X (also tried select delete_old_records1(31,'P','N');) and have this error:
SQL Error [42703]: ERROR: column "day1" does not exist
Where: PL/pgSQL function delete_old_records1(integer,character,character) line 11 at EXECUTE statement
SQL statement "SELECT "delete_old_records1"(31,'P','N')"
PL/pgSQL function inline_code_block line 2 at PERFORM