Question

I have following stored procedure

CREATE FUNCTION runMortalityModel(a_user_id integer) RETURNS integer AS $$
DECLARE
    t1 RECORD;
    t2 RECORD;
    numberOfDeaths integer;
BEGIN
    SELECT person.id personId, person.age, condprobmin, condprobmax, random() experiment
    INTO t1
    FROM person, mortality_cond_prob 
    WHERE (user_id = a_user_id) and
    (person.age = mortality_cond_prob.age);

    SELECT personId
    INTO t2
    FROM t1
    WHERE (tmp.condprobmin <= experiment) and (experiment <= tmp.condprobmax);

    SELECT COUNT(*)
    INTO numberOfDeaths
    FROM t2;

    RAISE 'numberOfDeaths=%', numberOfDeaths;

    EXECUTE 
        'DELETE '
        || 'FROM person '
        || 'WHERE person.id IN ' 
        || t2;

    RETURN numberOfDeaths;
END
$$ LANGUAGE plpgsql;

When I try to run this stored procedure using

SELECT runMortalityModel(1);

I get the error Relation »t1« doesn't exist.

How can I fix it?

Update 1: Changed the stored procedure declaration to

CREATE OR REPLACE FUNCTION runMortalityModel(a_user_id integer) RETURNS integer AS $$
DECLARE
    t1 RECORD;
    t2 RECORD;
    numberOfDeaths integer;
BEGIN
    EXECUTE 'SELECT person.id personId, person.age, condprobmin, condprobmax, random()  experiment '    
    || 'FROM person, mortality_cond_prob '
    || 'WHERE (user_id = ' || a_user_id || ') and '
    || '(person.age = mortality_cond_prob.age)'
    INTO t1;

    EXECUTE 'SELECT personId '
    || 'FROM ' || t1
    || ' WHERE (tmp.condprobmin <= experiment) and (experiment <= tmp.condprobmax)'
    INTO t2;

    EXECUTE 'SELECT COUNT(*) ' 
    || 'FROM ' || t2
    INTO numberOfDeaths;

    RAISE 'numberOfDeaths=%', numberOfDeaths;

    EXECUTE 
        'DELETE '
        || 'FROM person '
        || 'WHERE person.id IN ' 
        || t2;

    RETURN numberOfDeaths;
END
$$ LANGUAGE plpgsql;

Answer 1

I see several issues with original code:

1. You’re trying to use RECORD variable as a relation, you should do ... FROM (SELECT t1.*) s instead;
2. I see no point to select 1 record, then do a query on that record and then perform count(*), you will always have either 0 or 1 as a result.

You second version looks much better, go for it.