表结构
                id                name                 1                张三
                 1                李四
                 2                王五
需求是 创建一个视图 
                查询结果结构为 
 
                id                name               
                1                 张三, 李四
                2                 王五    
将相同id 的 name  用逗号拼接起来 ,oracle 数据库,请各位大侠帮帮忙 急