Question

我是sql的新手。我正在尝试运行以下查询

Create view ReturnCode as 
(
select ret_code, to_char(creation_dt,'DD-MON-YYYY HH24:MI:SS')“Created_Date”,current_timestamp,buff.log.* 
from buff.log
 WHERE ret_Code= '90'
 order by creation_dt
);

获取错误

must name this expression with a column alias

请帮助我在这里失踪

Answer 1

您必须在视图中为current_timestamp添加一个列名称。

隔离错误使其更加明显：

SQL> create view v1 as select current_timestamp from emp;
create view v1 as select current_timestamp from emp
                         *
ERROR at line 1:
ORA-00998: must name this expression with a column alias

（SQL * Plus甚至会向您显示必须命名的WHICH表达式 - 如果您使用的是SQL * Plus，它将在您的视图定义中执行相同的操作。）

为此表达式添加列名称：

SQL> create view v1 as select current_timestamp as current_ts from emp;

View created.

Answer 2

使用此：

CREATE VIEW ReturnCode
AS
   (SELECT t.ret_code,
           TO_CHAR (t.creation_dt, 'DD-MON-YYYY HH24:MI:SS') Created_Date,
           CURRENT_TIMESTAMP Curr_tmp,
           t.* 
      FROM buff.LOG t
     WHERE t.ret_Code = '90' 
     order by t.creation_dt
);

在oracle DB中创建视图时出错

2 个答案: