rspec/rules/S3874/plsql/rule.adoc

Functions with ``++OUT++`` parameters are complex to understand. Indeed, it is impossible to tell, just by looking at the function call, whether an argument is a input or output. Moreover, functions with ``++OUT++`` parameters cannot be called from SQL. It is better to either break such functions up into smaller ones, which each return a single value, or to return several values at once, by combining them in a collection, record, type, or table row.

== Noncompliant Code Example

----
SET SERVEROUTPUT ON

CREATE TABLE employee(
  firstName VARCHAR2(42),
  name VARCHAR2(42),
  phone VARCHAR2(42)
);

INSERT INTO employee VALUES ('John', 'Smith', '+1');

DECLARE
  firstName VARCHAR2(42);
  name VARCHAR2(42);
  phone VARCHAR2(42);

  -- This DOES NOT return the employee name
  FUNCTION getEmployeeInfos(firstName OUT VARCHAR2, phone OUT VARCHAR2) RETURN VARCHAR2 AS -- Non-Compliant, confusing
    name VARCHAR2(42);
  BEGIN
    SELECT firstName, name, phone INTO firstName, name, phone FROM employee;
    RETURN name;
  END;
BEGIN
  name := getEmployeeInfos(firstName, phone);

  DBMS_OUTPUT.PUT_LINE('firstName: ' || firstName);
  DBMS_OUTPUT.PUT_LINE('name: ' || name);
  DBMS_OUTPUT.PUT_LINE('phone: ' || phone);
END;
/
----

== Compliant Solution

----
SET SERVEROUTPUT ON

CREATE TABLE employee(
  firstName VARCHAR2(42),
  name VARCHAR2(42),
  phone VARCHAR2(42)
);

INSERT INTO employee VALUES ('John', 'Smith', '+1');

DECLARE
  emp employee%ROWTYPE;

  FUNCTION getEmployeeInfos RETURN employee%ROWTYPE AS -- Compliant
    emp employee%ROWTYPE;
  BEGIN
    SELECT * INTO emp FROM employee;
    RETURN emp;
  END;
BEGIN
  emp := getEmployeeInfos;

  DBMS_OUTPUT.PUT_LINE('firstName: ' || emp.firstName);
  DBMS_OUTPUT.PUT_LINE('name: ' || emp.name);
  DBMS_OUTPUT.PUT_LINE('phone: ' || emp.phone);
END;
/

DROP TABLE employee;
----