PL/SQL±í

/*
PL/SQL±í---table()º¯ÊýÓ÷¨£º
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oracleÄÚ´æ±íÔÚ²éѯºÍ±¨±íµÄʱºòÓõıȽ϶࣬ËüµÄËÙ¶ÈÏà¶ÔÎïÀí±íÒª¿ì¼¸Ê®±¶¡£
simple example£º
1¡¢table()½áºÏÊý×飺
*/
create or replace type t_test as object(
id integer,
rq date,
mc varchar2(60)
);
create or replace type t_test_table as table of t_test;
create or replace function f_test_array(n in number default null) return t_test_table
as
v_test t_test_table := t_test_table();
begin
for i in 1 .. nvl(n,100) loop
v_test.extend();
v_test(v_test.count) := t_test(i,sysdate,'mc'||i);
end loop;
return v_test;
end f_test_array;
/
select * from table(f_test_array(10));
select * from the(select f_test_array(10) from dual);
/*
2¡¢table()½áºÏPIPELINEDº¯Êý£º
*/
create or replace function f_test_pipe(n in number default null) return t_test_table PIPELINED
as
v_test t_test_table := t_test_table();
begin
for i in 1 .. nvl(n,100) loop
pipe row(t_test(i,sysdate,'mc'||i));
end loop;
return;
end f_test_pipe;
/
select * from table(f_test_pipe(20));
select * from the(select f_test_pipe(20) from dual);
/*
3¡¢table()½áºÏϵͳ°ü£º
*/
create table test (id varchar2(20));
insert into test values('1');
commit;
explain plan for select * from test;
select * from table(dbms_xplan.display);