获取所有实例化视图的计数

Question

I am trying to get a count from all materialized views in my database. This is what I have so far, but it is not returning the count -

DO
$$
DECLARE
    rec record;
    my_pk_new integer;
BEGIN
    FOR rec IN 
        SELECT matviewname
        FROM pg_matviews  
        limit 2
    LOOP
    EXECUTE ' SELECT count(*) from' || rec.matviewname
    INTO my_pk_new;
    END LOOP;
    RAISE NOTICE 'Calling (%)', my_pk_new;

END;
$$
LANGUAGE plpgsql;

This is what I would expect to see -

Matview A    2432
Matview B    453984

Answer 1

1) After from a space is missing. So you are executing the query

SELECT count(*) frommy_view

instead of

SELECT count(*) from my_view

So there is an error. On my system a default int value returned ( 1 )

2) Your RAISE NOTICE is outside the loop. So you are noticing only the very last query result. Put this into the loop body and it works.

DO $$
DECLARE
    rec record;
    my_pk_new integer;
BEGIN
    FOR rec IN 
        SELECT matviewname
        FROM pg_matviews  
        limit 2
    LOOP
        EXECUTE 'SELECT count(*) FROM ' || rec.matviewname
        INTO my_pk_new;

        RAISE NOTICE 'Calling (%)', my_pk_new;   
    END LOOP;       
END;
$$
LANGUAGE plpgsql;