Oracle语法和SQL语法的一些区别

一、SQL

ISNULL(字段名,替换值)

SUBSTRING(字段名,起始位置,截取长度)   

GETDATE()
  
YEAR(GETDATE())       

MONTH(GETDATE())         

DAY(GETDATE())

SELECT DATEPART(HOUR,GETDATE())       

SELECT DATEPART(MINUTE,GETDATE())      

SELECT DATEPART(SECOND,GETDATE())      

+ (连接符号)

'2013-03-29 11:40:28'

二、Oracle

NVL(字段名,替换值)

SUBSTR(字段名,起始位置,截取长度)

SELECT SYSDATE FROM DUAL

SELECT TO_CHAR(SYSDATE,'yyyy') FROM DUAL

SELECT TO_CHAR(SYSDATE,'MM')  FROM DUAL

SELECT TO_CHAR(SYSDATE,'dd')  FROM DUAL

SELECT TO_CHAR(SYSDATE,'hh')  FROM DUAL

SELECT TO_CHAR(SYSDATE,'mi')  FROM DUAL

SELECT TO_CHAR(SYSDATE,'ss')  FROM DUAL

||

TO_DATE('2013-03-29 11:40:28','yyyy/MM/dd hh:mi:ss')

原帖地址:http://blog.csdn.net/taomanman/article/details/8735698