How to return a record from an existing table from an Oracle PL/SQL function?

Question

I know it seems like a basic thing, but I\'ve never done this before.

I\'d like to return a single record from an existing table as the result of an Oracle PL/SQL fu

Answer 1

This is how I would do it. Variables/table-names/column-names are case-insensitive in Oracle, so I would use user_name instead of UserName.

CREATE TABLE users( UserName varchar2(20), OtherStuff VARCHAR2(20) );

Function update_and_get_user. Note that I return a ROWTYPE instead of Pipelined Tables.

CREATE OR REPLACE FUNCTION update_and_get_user(
  in_UserName   IN users.UserName%TYPE,
  in_OtherStuff IN users.OtherStuff%TYPE )
RETURN users%ROWTYPE
IS
  output_rec users%ROWTYPE;
BEGIN
  UPDATE users
  SET OtherStuff = in_OtherStuff
  WHERE UserName = in_UserName
    RETURNING UserName, OtherStuff
    INTO output_rec;
  RETURN output_rec;
END update_and_get_user;

And this is how you would call it. You can not check a ROWTYPE to be NULL, but you can check username for example.

DECLARE
  users_rec users%ROWTYPE;
BEGIN
  users_rec := update_and_get_user('user', 'stuff');
  IF( users_rec.username IS NOT NULL ) THEN
    dbms_output.put_line('FOUND: ' || users_rec.otherstuff);
  END IF;
END;

---

A solution using PIPED ROWS is below, but it doesn't work that way. You can not update tables inside a query.

SELECT * FROM TABLE(update_and_get_user('user', 'stuff'))

ORA-14551: cannot perform a DML operation inside a query

Solution would look like that:

CREATE OR REPLACE TYPE users_type
AS OBJECT
(
  username   VARCHAR2(20),
  otherstuff VARCHAR2(20)
)

CREATE OR REPLACE TYPE users_tab
   AS TABLE OF users_type;

CREATE OR REPLACE FUNCTION update_and_get_user(
  in_UserName   IN users.username%TYPE,
  in_OtherStuff IN users.otherstuff%TYPE )
RETURN users_tab PIPELINED
IS
  output_rec users%ROWTYPE;
BEGIN
  UPDATE users
  SET OtherStuff = in_OtherStuff
  WHERE UserName = in_UserName
    RETURNING username, otherstuff
    INTO output_rec;
  PIPE ROW(users_type(output_rec.username, output_rec.otherstuff));
END;