Morgan's Library Oracle Pipelined Table Functions

Oracle Pipelined Table Functions
Version 11.2

General Information

Data dictionary Objects

argument$	error$	source$
DBA	ALL	USER
dba_arguments	all_arguments	user_arguments
dba_errors	all_errors	user_errors
dba_object_size	all_object_size	user_object_size
dba_procedures	all_procedures	user_procedures
dba_source	all_source	user_source

System Privileges

alter any procedure
create any procedure
create procedure
debug any procedure
drop any procedure
execute any procedure

select any table

Syntax

CREATE OR REPLACE FUNCTION <schema_name>.<function_name>
(<argument> [IN | OUT | IN OUT] [NOCOPY] <data type>)
RETURN <data type>
[AUTHID <CURRENT USER | DEFINER>]
[<AGGREGATE | PIPELINED>]
[PARALLEL_ENABLE (PARTITION <argument> BY [<HASH, RANGE> (<column_list>), ANY])] IS

Tables And Data For Demo

Table Definition

CREATE TABLE stocktable (
ticker VARCHAR2(4),
open_price NUMBER(10),
close_price NUMBER(10));

Demo Data

INSERT INTO stocktable VALUES ('ORCL', 13, 16);
INSERT INTO stocktable VALUES ('MSFT', 35, 29);
INSERT INTO stocktable VALUES ('SUNW', 7, 11);
COMMIT;

Type Definition

CREATE OR REPLACE TYPE TickerType AS OBJECT (
ticker VARCHAR2(4),
pricetype VARCHAR2(1),
price NUMBER(10));
/

Create Table Type

CREATE OR REPLACE TYPE TickerTypeSet AS TABLE OF TickerType;
/

Create Package

CREATE OR REPLACE PACKAGE refcur_pkg IS
TYPE refcur_t IS REF CURSOR RETURN StockTable%ROWTYPE;
END refcur_pkg;
/

Create Table Function

CREATE OR REPLACE FUNCTION stockpivot(
p refcur_pkg.refcur_t)
RETURN TickerTypeSet AUTHID DEFINER PIPELINED IS
out_rec TickerType := TickerType(NULL,NULL,NULL);
in_rec   p%ROWTYPE;
BEGIN
LOOP
    FETCH p INTO in_rec;
    EXIT WHEN p%NOTFOUND;

    out_rec.ticker := in_rec.Ticker;
    out_rec.pricetype := 'O';
    out_rec.price := in_rec.Open_Price;
    PIPE ROW(out_rec);

    out_rec.PriceType := 'C';
    out_rec.price := in_rec.Close_Price;
    PIPE ROW(out_rec);
END LOOP;
CLOSE p;
RETURN;
END stockpivot;
/

desc stockpivot

set linesize 121
col pipelined format a10

SELECT object_name, pipelined, authid
FROM user_procedures;

Sample Query

SELECT *
FROM TABLE(stockpivot(CURSOR(SELECT * FROM StockTable)));

Generate Date List

CREATE OR REPLACE TYPE date_array AS TABLE OF DATE;
/

CREATE OR REPLACE FUNCTION date_table(sdate DATE, edate DATE)
RETURN date_array AUTHID CURRENT_USER PIPELINED AS

BEGIN
FOR i IN 0 .. (edate - sdate) LOOP
PIPE ROW(sdate + i);
END LOOP;
RETURN;
END date_table;
/

desc date_table

SELECT object_name, pipelined, authid
FROM user_procedures;

SELECT *
FROM TABLE(CAST(date_table(TRUNC(SYSDATE-30), TRUNC(SYSDATE))
AS date_array));

-- joined with another table

CREATE TABLE testdata (
datecol DATE,
someval NUMBER);

INSERT INTO testdata VALUES (TRUNC(SYSDATE-25), 25);
INSERT INTO testdata VALUES (TRUNC(SYSDATE-20), 20);
INSERT INTO testdata VALUES (TRUNC(SYSDATE-15), 15);
INSERT INTO testdata VALUES (TRUNC(SYSDATE-10), 10);
INSERT INTO testdata VALUES (TRUNC(SYSDATE-5), 5);
COMMIT;

SELECT * FROM testdata;

SELECT da.column_value AS DATECOL, td.someval
FROM TABLE(CAST(date_table(TRUNC(SYSDATE-30), TRUNC(SYSDATE))
AS date_array)) da, testdata td
WHERE da.COLUMN_VALUE = td.datecol(+);

Note: A SQL alternative would be:
SELECT iv.datecol, td.someval
FROM (
WITH dates AS (SELECT SYSDATE-30 dt_start, SYSDATE dt_end FROM dual)
SELECT dt_start+rownum-1 AS DATECOL
FROM dates
CONNECT BY LEVEL <= dt_end-dt_start) iv, testdata td
WHERE TRUNC(iv.datecol) = TRUNC(td.datecol (+))
ORDER BY datecol;

Turning a comma delimited list into a row-by-row output

CREATE OR REPLACE TYPE str_array AS TABLE OF VARCHAR2(10);
/

CREATE OR REPLACE FUNCTION ptf(stringin VARCHAR2) RETURN str_array PIPELINED IS
i PLS_INTEGER;
str VARCHAR2(100);
tab sys.dbms_utility.uncl_array;
BEGIN
str := '"' || REPLACE(stringin, ',', '","') || '"';
sys.dbms_utility.comma_to_table(str, i, tab);

FOR j IN 1 .. 5 LOOP
PIPE ROW(TRANSLATE(tab(j),'A"','A'));
END LOOP;
RETURN;
END ptf;
/

SELECT *
FROM TABLE(CAST(ptf('1001,1002,1003,1004,1005')
AS str_array));

Tom Kyte's demo

Not sure where or when I got this but it looks like something Tom would have written so I will give that attribution until some other origin is established.

CREATE OR REPLACE TYPE virtual_table_type AS TABLE OF number;
/

CREATE OR REPLACE FUNCTION virtual_table(p_num_rows IN NUMBER)
RETURN virtual_table_type AUTHID CURRENT_USER PIPELINED IS
BEGIN
FOR i IN 1 .. p_num_rows LOOP
    dbms_output.put_line('going to pipe');
    PIPE ROW( i );
    dbms_output.put_line('done pipeing');
END LOOP;
RETURN;
END virtual_table;
/

SELECT * FROM TABLE(virtual_table(5));
SELECT * FROM TABLE(virtual_table(10));

set serveroutput on

BEGIN
FOR x IN (SELECT * FROM TABLE(virtual_table(10))) LOOP
    dbms_output.put_line('Fetching.... ' || x.column_value);
END LOOP;
END;
/

CREATE OR REPLACE TYPE myScalarType AS OBJECT (
c1 VARCHAR2(9),
c2 VARCHAR2(9),
c3 VARCHAR2(9),
c4 VARCHAR2(9),
c5 VARCHAR2(9),
c6 VARCHAR2(9),
c7 VARCHAR2(9));
/

desc myScalarType

CREATE OR REPLACE TYPE myArrayType AS TABLE OF myScalarType;
/

desc myArrayType

CREATE OR REPLACE FUNCTION pivot(p_cur IN sys_refcursor)
RETURN myArrayType AUTHID CURRENT_USER PIPELINED IS
l_c1 varchar2(4000);
l_c2 varchar2(4000);
l_last varchar2(4000);
l_cnt number ;
l_data myScalarType;
BEGIN
LOOP
    FETCH p_cur INTO l_c1, l_c2;
    EXIT WHEN p_cur%NOTFOUND;

    IF (l_last IS NULL OR l_c1 <> l_last) THEN
      IF (l_data IS NOT NULL) THEN
        pipe row(l_data);
      END IF;

      l_data := myScalarType(l_c1, l_c2, NULL, NULL, NULL, NULL, NULL);
      l_cnt := 3;
      l_last := l_c1;
    ELSE
      CASE l_cnt
      WHEN 3 THEN l_data.c3 := l_c2;
      WHEN 4 THEN l_data.c4 := l_c2;
      WHEN 5 THEN l_data.c5 := l_c2;
      WHEN 6 THEN l_data.c6 := l_c2;
      WHEN 7 THEN l_data.c7 := l_c2;
      ELSE raise program_error;
      END CASE;

      l_cnt := l_cnt+1;
    END IF;
END LOOP;

IF (l_data IS NOT NULL) THEN
    PIPE ROW(l_data);
END IF;
CLOSE p_cur;
RETURN;
END pivot;
/

SELECT *
FROM TABLE(pivot(CURSOR(
SELECT deptno, ename FROM scott.emp ORDER BY deptno)));

SELECT *
FROM TABLE(pivot(
CURSOR(SELECT deptno, hiredate FROM scott.emp ORDER BY deptno)));

Parallel Enable Demo

CREATE OR REPLACE PACKAGE pkg_test IS
TYPE rt_Src IS RECORD(id NUMBER, col1 VARCHAR2(100));
TYPE rc_Src IS REF CURSOR RETURN rt_Src;

TYPE rt_Out IS RECORD(id NUMBER, col1 VARCHAR2(100), sid NUMBER);
TYPE tt_Out IS TABLE OF rt_Out;

FUNCTION f_Pipe_Any(airc_Src IN rc_Src) RETURN tt_Out PIPELINED
PARALLEL_ENABLE(PARTITION airc_Src BY ANY);

FUNCTION f_Pipe_Hash(airc_Src IN rc_Src) RETURN tt_Out PIPELINED
PARALLEL_ENABLE(PARTITION airc_Src BY HASH(id));

FUNCTION f_Pipe_Range(airc_Src IN rc_Src) RETURN tt_Out PIPELINED
PARALLEL_ENABLE(PARTITION airc_Src BY RANGE(id));

END;
/

CREATE OR REPLACE PACKAGE BODY pkg_test IS
FUNCTION f_Pipe_Any(airc_Src IN rc_Src) RETURN tt_Out PIPELINED
PARALLEL_ENABLE(PARTITION airc_Src BY ANY) IS
lr_Src rt_Src;
lr_Out rt_Out;
BEGIN
LOOP
    FETCH airc_Src INTO lr_Src;
    EXIT WHEN airc_Src%NOTFOUND;

    SELECT sid
    INTO lr_Out.sid
    FROM v$mystat
    WHERE ROWNUM = 1;

    lr_Out.id := lr_Src.id;
    lr_Out.col1 := lr_Src.col1;
    PIPE ROW(lr_Out);
END LOOP;
CLOSE airc_Src;
END;

FUNCTION f_Pipe_Hash (airc_Src IN rc_Src) RETURN tt_Out PIPELINED
PARALLEL_ENABLE(PARTITION airc_Src BY HASH(id)) IS
lr_Src rt_Src;
lr_Out rt_Out;
BEGIN
LOOP
    FETCH airc_Src INTO lr_Src;
    EXIT WHEN airc_Src%NOTFOUND;

    SELECT sid
    INTO lr_Out.sid
    FROM v$mystat
    WHERE ROWNUM = 1;

    lr_Out.id := lr_Src.id;
    lr_Out.col1 := lr_Src.col1;
    PIPE ROW(lr_Out);
END LOOP;
CLOSE airc_Src;
END;

FUNCTION f_Pipe_Range (airc_Src IN rc_Src) RETURN tt_Out PIPELINED
PARALLEL_ENABLE(PARTITION airc_Src BY RANGE(id)) IS
lr_Src rt_Src;
lr_Out rt_Out;
BEGIN
LOOP
    FETCH airc_Src INTO lr_Src;
    EXIT WHEN airc_Src%NOTFOUND;

    SELECT sid
    INTO lr_Out.sid
    FROM v$mystat
    WHERE ROWNUM = 1;

    lr_Out.id := lr_Src.id;
    lr_Out.col1 := lr_Src.col1;
    PIPE ROW(lr_Out);
END LOOP;
CLOSE airc_Src;
END;
END;
/

CREATE TABLE dt_src (
id   NUMBER,
col1 VARCHAR2(100));

INSERT INTO dt_src
SELECT ROWNUM, TO_CHAR(ROWNUM)
FROM dual
CONNECT BY LEVEL <= 100000;

CREATE TABLE dt_out (
id       NUMBER,
col1     VARCHAR2(100),
sid      NUMBER,
src_proc VARCHAR2(32));

set autotrace trace stat explain

INSERT INTO dt_out
SELECT id, col1, sid, 'ANY'
FROM TABLE (pkg_test.f_Pipe_Any(CURSOR(SELECT --+parallel(dt_src)
id, col1 FROM dt_src)));

INSERT INTO dt_out
SELECT id, col1, sid, 'HASH'
FROM TABLE(pkg_test.f_Pipe_Hash(CURSOR(SELECT --+parallel(dt_src)
id, col1 FROM dt_src)));

INSERT INTO dt_out
SELECT id, col1, sid, 'RANGE'
FROM TABLE (pkg_test.f_Pipe_Range(CURSOR(SELECT --+parallel(dt_src)
id, col1 FROM dt_src)));

set autotrace off

SELECT COUNT(*), sid, src_proc
FROM dt_out
GROUP BY sid, src_proc
ORDER BY sid, src_proc;

Drop Pipelined Table Functions

Drop PTF

DROP FUNCTION <function_name>;

DROP FUNCTION ptf;

DROP FUNCTION pivot;

DROP FUNCTION stockpivot;

Related Topics
Anonymous Block
Exception Handling
Functions
NO_DATA_NEEDED
Pseudocolumns
Tables
Types

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