求一个Oracle函数 - Oracle / 开发

实现功能
输入"2008-12-21 12:20:20"
输出"2008-12-21 12:00:00"

我写的有问题


CREATE FUNCTION getdatehour(IDE date)
RETURN date as OED date;
BEGIN
OED:=cast(to_char(IDE,'YY')+'-'+to_char(IDE,'MM')+'-'+to_char(IDE,'DD')+' '+to_char(IDE,'HH24')+':00:00' as date);
return ODE;
END;

谁能给我个正确的函数啊

---

CREATE FUNCTION getdatehour(IDE date)
RETURN date as OED date;
BEGIN
OED:=substr(IDE,1,14)||00:00;
return ODE;
END;

---

CREATE OR REPLACE FUNCTION getdatehour(IDE date)
RETURN date
is
 OED date;
BEGIN
OED:=trunc(IDE,'hh');
return OED;
END;

select getdatehour(sysdate) from dual;

---

1楼报错:

alter FUNCTION getdatehour(IDE date)
  *
ERROR 1 :
ORA-00922: 


SP2-0552: "00"

---

SQL code:

CREATE or replace FUNCTION getdatehour(IDE date)
RETURN date as
ODE date;
BEGIN
ODE := to_date(to_char(ide, 'yyyy-mm-dd hh24') || '00:00','yyyy-mm-dd hh24:mi:ss');
return ODE;
END;


测试代码：
SQL code:

declare
d date := sysdate;
begin
d := getdatehour(d);
db