Run SQL statements in PL/pgSQL only if a row doesn't exist

Question

I want to do something like this in a PL/pgSQL function in Postgres 9.6:

INSERT INTO table1 (id, value) VALUES (1, \'a\') ON CONFLICT DO NOTHING;
--- If the          


        

Answer 1

The easiest and reliable way is with the especial variable FOUND, this way:

INSERT INTO table1 (id, value) values (1, ‘a’) on conflict do nothing;

IF FOUND THEN

--success

ELSE

--failure

END IF;

Here is the documentation of diagnosing a statement https://www.postgresql.org/docs/9.6/static/plpgsql-statements.html