在mysql用来对字符型的时间日期格式化我们常用CONVERT()函数来操作,下面我来给各位朋友详细介绍CONVERT()函数的使用方法,大家可参考。
格式:
CONVERT(data_type,expression[,style])
说明:
此样式一般在时间类型(datetime,smalldatetime)与字符串类型(nchar,nvarchar,char,varchar)
相互转换的时候才用到.
例子:
代码如下 | 复制代码 |
SELECT CONVERT(varchar(30),getdate(),101) now |
结果为:
now
|09/15/2001
代码如下 | 复制代码 |
Select CONVERT(varchar(100), GETDATE(), 0) --05 16 2006 10:57AM |
style数字在转换时间时的含义如下:
Style(2位表示年份)
Style(4位表示年份)
输入输出格式
0
100
mon dd yyyy hh:miAM(或PM)
1
101
mm/dd/yyyy
2
102
yyyy-mm-dd
3
103
dd/mm/yyyy
4
104
dd-mm-yyyy
5
105
dd-mm-yyyy
6
106
dd mon yyyy
7
107
mon dd,yyyy
8
108
hh:mm:ss
9
109
mon dd yyyy hh:mi:ss:mmmmAM(或PM)
10
110
mm-dd-yy
11
111
yy/mm/dd
12
112
yymmdd
13
113
dd mon yyyy hh:mi:ss:mmm(24小时制)
14
114
hh:mi:ss:mmm(24小时制)
20
120
yyyy-mm-dd hh:mi:ss(24小时制)
21
121
yyyy-mm-dd hh:mi:ss:mmm(24小时制)
注意了convert与cast的区别了,这里简单说明一下
convert一般用于值,小数之间转换;
cast一般用于小数转数值和字符型

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