Hive中date_format()函数的用法

一、date_format的用法

1. 作用

格式化日期时间，将日期按照自己想要的格式输出。

2. 语法

date_format(date, format)：date参数是合法的日期，format参数是规定日期输出的格式。

3. 示例

SELECT CURRENT_DATE AS time1, DATE_FORMAT(CURRENT_DATE, 'yyyyMMdd') AS time2;

--输出结果
time1		time2
2022-12-06	20221206

4. 常用的符号标识

可参考Hive官网中 date_format() 函数的描述。

Letter	Date or Time Component	Presentation	Examples
G	Era designator	Text	AD
y	Year	Year	1996; 96
Y	Week year	Year	2009; 09
M	Month in year	Month	July; Jul; 07
w	Week in year	Number	27
W	Week in month	Number	2
D	Day in year	Number	189
d	Day in month	Number	10
F	Day of week in month	Number	2
E	Day name in week	Text	Tuesday; Tue
u	Day number of week (1 = Monday, …, 7 = Sunday)	Number	1
a	Am/pm marker	Text	PM
H	Hour in day (0-23)	Number	0
k	Hour in day (1-24)	Number	24
K	Hour in am/pm (0-11)	Number	0
h	Hour in am/pm (1-12)	Number	12
m	Minute in hour	Number	30
s	Second in minute	Number	55
S	Millisecond	Number	978
z	Time zone	General time zone	Pacific Standard Time; PST; GMT-08:00
Z	Time zone	RFC 822 time zone	-0800
X	Time zone	ISO 8601 time zone	-08; -0800; -08:00

获取年月日时分秒：

SELECT DATE_FORMAT('2022-07-04 15:10:25', 'yyyy-MM-dd HH:mm:ss') AS time;