CREATE TYPE www_type AS (
    object_id integer,
    parent_id integer,
    type_id integer,
    type_name varchar(100),
    dvalue date,
    tvalue time,
    bvalue boolean,
    mvalue varchar(20),
    ivalue integer,
    sortvalue varchar(100),
    svalue varchar(6000)
);

CREATE TABLE www_temp(
       object_id integer,
       parent_id integer,
       step integer,
       UNIQUE (object_id, parent_id, step)
);

CREATE OR REPLACE FUNCTION getwwwdata()  
    RETURNS SETOF www_type
    LANGUAGE 'plpgsql'
    AS'
DECLARE
    i integer;
    var_rec RECORD;
BEGIN
    DELETE FROM www_temp;

    INSERT INTO www_temp
    SELECT
		o1.object_id,
		NULL AS parent_id,
		1 AS step
	FROM
		object o1
	WHERE
		o1.type_id IN (
			SELECT
				type_id
			FROM
				obj_types
			WHERE
				name IN (''data'', ''free'', ''noname'')
	        ) AND
		o1.dvalue BETWEEN (date ''2004-11-29'') AND (date ''2004-11-29'' + integer ''7'');

	LOOP
        SELECT object_id FROM www_temp WHERE step=i-1;
        IF NOT FOUND THEN
            EXIT;  -- exit loop
        END IF;
        IF i>10 THEN
            EXIT;  -- exit loop
        END IF;

        INSERT INTO www_temp
	    SELECT
                o2o.obj2 AS object_id,
                o2o.obj1 AS parent_id,
                i AS step
	       FROM
                obj_to_obj o2o
	    WHERE
                o2o.obj1 IN (SELECT object_id FROM www_temp WHERE step=i-1);

        i:=i+1;
    END LOOP;
    
    FOR var_rec IN 
        SELECT
            o1.object_id,
            tmp.parent_id,
            o1.type_id,
            ot.name AS type_name,
            o1.dvalue,
            o1.tvalue,
            o1.bvalue,
            o1.mvalue,
            o1.ivalue,
            o1.sortvalue,
            CAST(o1.svalue AS varchar(6000))
        FROM
            object o1
        INNER JOIN
            obj_types ot
        ON
            ot.type_id=o1.type_id
        INNER JOIN
            (SELECT * FROM www_temp) tmp
        ON
            o1.object_id=tmp.object_id
    LOOP
        RETURN NEXT var_rec;
    END LOOP;
    
    RETURN;
END;
';

CREATE TABLE "public"."obj_types" (
  "type_id" SERIAL, 
  "name" VARCHAR( 100 ) NOT NULL,
  CONSTRAINT "obj_types_pkey" PRIMARY KEY("type_id")
) WITH OIDS;

CREATE TABLE "public"."object" (
  "object_id" SERIAL, 
  "type_id" INTEGER, 
  "reg_date" TIMESTAMP, 
  "svalue" TEXT, 
  "dvalue" DATE, 
  "tvalue" TIME WITHOUT TIME ZONE, 
  "bvalue" BOOLEAN, 
  "ivalue" INTEGER, 
  "mvalue" VARCHAR( 20 ), 
  "sortvalue" VARCHAR( 100 ), 
  "city" INTEGER, 
  "check_date" TIMESTAMP WITHOUT TIME ZONE, 
  CONSTRAINT "object_pkey" PRIMARY KEY("object_id")
) WITH OIDS;

CREATE TABLE "public"."obj_to_obj" (
  "obj1" INTEGER NOT NULL, 
  "obj2" INTEGER NOT NULLб
  CONSTRAINT "o_to_o_con2" CHECK (obj1 <> obj2)
) WITH OIDS;

select * from "public"."getwwwdata" ();
ERROR:  SELECT query has no destination for result data
HINT:  If you want to discard the results, use PERFORM instead.
CONTEXT:  PL/pgSQL function "getwwwdata" line  28  at SQL statement

PERFORM 'SELECT object_id FROM www_temp WHERE step=' || (i- 1 )::text|| ';';

PERFORM (SELECT object_id FROM www_temp WHERE step=(i- 1 ));

ERROR:  more than one row returned by a subquery used as an expression
CONTEXT:  PL/pgSQL function "getwwwdata" line  28  at perform

PERFORM (SELECT object_id FROM www_temp WHERE step=(i- 1 ) LIMIT  1 );