Crosstab function

Hi Friends,

Could somebody help me with crosstab function ? I have warehouse table:

CREATE TABLE tblwarehouse (

id integer NOT NULL,

warehousename character varying(20)

);

COPY tblwarehouse (id, warehousename) FROM stdin;

2 OFFICE

3 STORE2

\.

And product table :

CREATE TABLE tblproduct (

id serial NOT NULL,

produkid text,

warehouseid integer,

onhand integer

);

COPY tblproduct (produkid, warehouseid, onhand) FROM stdin;

2791404000014 2 10

2791404000021 3 10

2791404000014 3 45

\.

I need crosstab function to display record from tblproduct like this :

PRODUKID | OFFICE | STORE2 | TOTAL

---------------+--------+--------+ ------

2791404000014 | 10 | 45 | 55

2791404000021 | 0 | 10 | 10

The crosstab warehouse column name (OFFICE & Store2) is taken from
tblwarehouse so when user add warehouse, crosstab column name will change
automatically. And also each row has total qty.

Thanks in advance !