cast with collections
using multiset with a varray
cast(multiset() as )
create or replace type cust_address_t
oid '53a970b3f5024bec8efd4f84cad5e09e'
as object (
street_address varchar2(40),
postal_code varchar2(10),
city varchar2(30),
state_province varchar2(2),
country_id varchar(2));
/create or replace type address_book_t as table of cust_address_t;
/create table cust_address (
custno number(10),
street_address varchar2(40),
postal_code varchar2(10),
city varchar2(30),
state_province varchar2(2),
country_id varchar2(2));
insert into cust_address
values (1,'123 main st.','98040','mercer island','wa','us');
insert into cust_address
values (2,'1 broadway','10202','new york','ny','us');
insert into cust_address
values (3,'2462 edgar crest','v6l 2c4','vancouver','bc','cn');
commit;
create table cust_short (
custno number(10),
name varchar2(30));
insert into cust_short values (1,'morgan');
insert into cust_short values (2,'cline');
insert into cust_short values (3,'scott');
select s.custno, s.name,
cast(multiset(select ca.street_address,
ca.postal_code,
ca.city,
ca.state_province,
ca.country_id
from cust_address ca
where s.custno = ca.custno) as address_book_t)
from cust_short s;
using multiset with a pl/sql table
cast(multiset() as )
create or replace type project_table_t as
table of varchar2(25);
/create table projects (
person_id number(10),
project_name varchar2(20));
create table pers_short (
person_id number(10),
last_name varchar2(25));
insert into projects values (1, 'teach');
insert into projects values (1, 'code');
insert into projects values (2, 'code');
insert into pers_short values (1, 'morgan');
insert into pers_short values (2, 'cline');
insert into pers_short values (3, 'scott');
commit;
select * from projects;
select * from pers_short;
select e.last_name,cast(multiset(
select p.project_name
from projects p
where p.person_id = e.person_id
order by p.project_name) as project_table_t)
from pers_short e;
using multiset with a multi-column collection
cast(multiset() as )
create or replace type uob_type as object (
object_name varchar2(128), object_type varchar2(18));
/create or replace type t_uob_type as table of uob_type;
/set serveroutput on
declare
x t_uob_type;
begin
selectcast(multiset(
select object_name, object_type
from user_objects
where rownum <10) as t_uob_type)
into x
from dual;
for i in 1 .. x.count
loop
dbms_output.put_line(x(i).object_name || ' - '
|| x(i).object_type);
end loop;
end;
/converting a varray type column into a nested table
cast(as )
create or replace type district_t as object (
region_no number(2),
title varchar2(35),
cost number(7,2));
/create type distlist_t as table of district_t;
/create type districtlist as varray(10) of district_t;
/create table region_tab (
reg_id number(2),
reg_name varchar2(15),
district districtlist);
set describe depth all linenum on indent on
desc region_tab
select * from region_tab;
insert into region_tab
values(30, 'northwest',
districtlist (district_t(1, 'alaska', 3250),
district_t(2, 'washington', 12350),
district_t(3, 'oregon', 2750),
district_t(4, 'idaho', 1425)));
insert into region_tab
values(40, 'southwest',
districtlist (district_t(1, 'arizona', 3250),
district_t(2, 'california', 12350),
district_t(3, 'nevada', 2750),
district_t(4, 'new mexico', 1425)));
selectcast(s.district as distlist_t)
from region_tab s
where s.reg_id = 30;
cast with dates
date
cast(as )
selectcast('01-jan-2004' as date) cdate
from dual;
timestamp
cast(as )
selectcast(sysdate as timestamp with local time zone) dtwtz
from dual;
cast with numbers
number
cast(as )
select 1 +cast(3.14 * 0.152 as number(10,7)) floating
from dual;
cast with strings
varchar2
cast(as )
select object_name
from user_objects;
selectcast(object_name as varchar2(30)) obj_name
from user_objects;
related topics
types
varrays
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