今天学习,就把博客作为自己的学习笔记吧,有兴趣的博友可以一起讨论:

在TERADATA中可以将DATE看做整数来对待,但不容许无效日期存在.

计算公式;  (year-1900)*1000  +  month*100 + day

例如:计算某个人的年龄  (date -birthday)/365

 日期函数举例:                                                 结果

extract()   举例:  select date                              2007/01/12

                  select extract(year from date)              2007

                  select extract(month from date +2);         03

                  select extract ( day from  date +30);     invid day

                  select time                               12:24:35

                  select extract(hour  from time)           12