return as locator作用,看这里http://www.zdnet.com.cn/developer/code/story/0,2000081534,39033680,00.htm 报错: (指向*content nested_content,) 必须指定嵌套表列或属性的表名称;
create or replace type content_t as object (content varchar2,page number); 有问题varchar2(?)
上面创建表是该为:create table book ( bid char(4) not null, bname varchar(13), authors nested_author, price double precision, providerid providerid_t, content nested_content, cover blob, inventory number, stockplace blob, primary key(bid) )nested table authors store as nested_authors_list return as locator nested table content store as nested_content_list return as locator / 表已创建
providerid这个字段不定有多少个值,我用varray(20)定义又怕不够,难道要定varray(100)?会不会占用很多空间,或者有没有其它更好的办法? why not use nested table? http://download-west.oracle.com/docs/cd/B10501_01/appdev.920/a96594/adobjdes.htm#451015
最后两行这样写就对了,被一个小小的分号害惨:-( nested table authors store as nested_authors_list return as locator nested table content store as nested_content_list return as locator;
to dou1204(greenbird) : providerid只有一个字段也用嵌套表?不过为了解决个数问题似乎只有这样了?!
报错:
(指向*content nested_content,)
必须指定嵌套表列或属性的表名称;
有问题varchar2(?)
(
bid char(4) not null,
bname varchar(13),
authors nested_author,
price double precision,
providerid providerid_t,
content nested_content,
cover blob,
inventory number,
stockplace blob,
primary key(bid)
)nested table authors store as nested_authors_list return as locator
nested table content store as nested_content_list return as locator
/
表已创建
why not use nested table?
http://download-west.oracle.com/docs/cd/B10501_01/appdev.920/a96594/adobjdes.htm#451015
nested table authors store as nested_authors_list return as locator
nested table content store as nested_content_list return as locator;
providerid只有一个字段也用嵌套表?不过为了解决个数问题似乎只有这样了?!