一个数型数据库表如何得到相应的list!!!!
CREATE TABLE item
(
id int8 NOT NULL,
parentid int8 NOT NULL,
title varchar(50),
icon varchar(200),
CONSTRAINT pk_item PRIMARY KEY (id)
);
CREATE TABLE forward
(
id int8 NOT NULL,
parentid int8 NOT NULL,
title varchar(50),
href varchar(50),
linktype varchar(50),
target varchar(50),
CONSTRAINT pk_forward PRIMARY KEY (id)
) ;
----item节点
ALTER TABLE item
ADD CONSTRAINT fk_item FOREIGN KEY (parentid)
REFERENCES item (id)
ON UPDATE RESTRICT ON DELETE RESTRICT;
----forward链接
ALTER TABLE forward
ADD CONSTRAINT fk_forward FOREIGN KEY (parentid)
REFERENCES item (id)
ON UPDATE RESTRICT ON DELETE RESTRICT;
说明:这里面存在:item是个对象,然后它包含forward一个对象
然后再把他们封装到一个大的对象中,所以这就存在一个怎么查找和构造的问题!!