如何在 sql (oracle) 中操作 VARRAYS？

Question

假设我正在使用一个 table 人，并且这些人可能有多个姓氏，因此该属性应该是一个包含 3 个元素的数组（例如，这与存储姓氏的位置无关），这里是一个简单的 sql 用于创建姓氏类型，table 人并在 oracle 的 sql developper (11G XE):

中添加示例行

create type lastn as varray(3) of varchar2(10);
CREATE TABLE person
(
    ID NUMBER NOT NULL 
  , last_name lastn
  , CONSTRAINT EXEMPLE_PK PRIMARY KEY 
      (
          ID 
      )
     ENABLE 
);

insert into person values(1,lastn('dani','bilel'));

我知道如何一次更新所有姓氏，但我需要保留现有姓氏并添加其他姓氏，或者删除一个姓氏而不影响其他姓氏。简而言之，我希望我的代码像（我不熟悉PL/SQL）：

insert into table
    (select last_name from example where id=1)
   values lastn('new');

在这种情况下，我想让名字为 'bilel'，第二个姓氏为 last_name 的人为 'dani'

select * from person where id in (select id from pernom p,table(p.last_name) 
where column_value(1)='bilel' and column_value(2)='dani');

我知道它不是那样工作的，但我想知道那种情况下的 CRUD(create update delete) 语句。和 select 在 where 语句中使用 varray 的语句。

感谢您的回复。

Answer 1

From the docs:

Oracle does not support piecewise updates on VARRAY columns. However, VARRAY columns can be inserted into or updated as an atomic unit.

如此处的示例所示，您可以改为通过 PL/SQL 操作集合；包括向数组中添加一个元素：

declare
  l_last_name lastn;
begin
  select last_name into l_last_name
  from person where id = 1;

  l_last_name.extend();
  l_last_name(l_last_name.count) := 'third';

  update person
  set last_name = l_last_name
  where id = 1;
end;
/

PL/SQL procedure successfully completed.

select last_name from person where id = 1;

LAST_NAME                                         
--------------------------------------------------
LASTN('dani', 'bilel', 'third')

您也可以通过 cast(multiset(...) as ...):

-- rollback; to reverse PL/SQL block actions above

update person p
set last_name = cast(multiset(
    select column_value
    from table (last_name)
    union all
    select 'third' from dual
  ) as lastn)
where id = 1;

1 row updated.

select last_name from person where id = 1;

LAST_NAME                                         
--------------------------------------------------
LASTN('dani', 'bilel', 'third')

这会将现有的 last_name 值分解为多行，合并为一个新值，然后将组合结果转换回您的 varray 类型。

您可以用类似的方式删除或更新元素：

update person p
set last_name = cast(multiset(
    select column_value
    from table (last_name)
    where column_value != 'bilel'
  ) as lastn)
where id = 1;

1 row updated.

select last_name from person where id = 1;

LAST_NAME                                         
--------------------------------------------------
LASTN('dani', 'third')

update person p
set last_name = cast(multiset(
    select case column_value when 'third' then 'second' else column_value end
    from table (last_name)
  ) as lastn)
where id = 1;

1 row updated.

select last_name from person where id = 1;

LAST_NAME                                         
--------------------------------------------------
LASTN('dani', 'second')

Answer 2

对于 select 语句，我找到了解决方案，它是这样的：

select * from person p where id in (select id from table(p.last_name) where 
column_value='bilel' intersect select id from table(p.last_name) where 
column_value='dani');

或

select * from agent ag where id in (select id from table(ag.prenom) 
t1,table(ag.prenom) t2,table(ag.prenom) t3 where t1.column_value='bilel' and 
t2.column_value='dani' and t3.column_value='third');

如何在 sql (oracle) 中操作 VARRAYS？

How to manipulate VARRAYS in sql (oracle)?

sql

object-relational-model

oracle11g

varray