下面的代碼返回年度僱員誕生:如何創建或更換功能改成Convert_Year_to_Year到Day_to_Day
CREATE OR REPLACE FUNCTION Convert_Year_to_Year (Convert_Date IN Date)
RETURN Varchar2 AS
BEGIN
RETURN (To_Char (Convert_Date, ‘YEAR’));
END;
/
當我使用SELECT命令檢索數據,以下輸出顯示:
Select employee_id, hiredate, Convert_year_to_year (hiredate) AS Year_Hired
FROM employees;
EMPLOYEE_ID HIREDATE YEAR_HIRED
1 12/17/2007 TWO THOUSAND SEVEN
2 02/20/2008 TWO THOUSAND EIGHT
3 02/22/2008 TWO THOUSAND EIGHT
4 04/02/2008 TWO THOUSAND EIGHT
5 09/28/2008 TWO THOUSAND EIGHT
6 05/01/2008 TWO THOUSAND EIGHT
7 06/09/2008 TWO THOUSAND EIGHT
8 12/09/2008 TWO THOUSAND EIGHT
9 09/08/2007 TWO THOUSAND SEVEN
10 01/12/2007 TWO THOUSAND SEVEN
- 我怎樣才能改變 「YEAR_HIRED」 以數字今年來說2007年?
- 如何更改「YEAR_HIRED」以返回當天的名稱以及星期幾?
此外,如果我想結合所有的RETURN,我該如何編寫代碼?下面沒有工作
CREATE OR REPLACE FUNCTION Convert_Year_to_Year (Convert_Date IN Date)
RETURN Varchar2 AS
BEGIN
RETURN (To_Char (Convert_Date, 'YYYY'),
RETURN (To_Char (Convert_Date, 'DAY'),
RETURN (To_Char (Convert_Date, 'D'));
END;
/
EMPLOYEE_ID HIREDATE YEAR_HIRED DAY_HIRED NUMERICAL_DAY_OF_WEEK
1 12/17/2007 2007 MONDAY 1
2 02/20/2008 2008 WEDNESDAY 3
3 02/22/2008 2008 FRIDAY 5
4 04/02/2008 2008 WEDNESDAY 5
5 09/28/2008 2008 SUNDAY 7
什麼「一天的名字」和一週中的哪一天? – sstan
你想返回3個不同的值(你需要3個獨立的函數)嗎?或者你想要1位大的返回值將3位信息連接在一起嗎? – sstan