发行说明
下列函数是“Appendix D. Extended Scalar Functions”的“Date and Time Functions”一节中所缺少的函数:
- DAYOFWEEK_ISO( date_exp )
- Returns the day of the week in date_exp as
an integer value in the range 1-7, where 1 represents Monday. Note the difference
between this function and the DAYOFWEEK() function, where 1 represents Sunday.
- WEEK_ISO( date_exp )
- Returns the week of the year in date_exp
as an integer value in the range of 1-53. Week 1 is defined as the first week
of the year to contain a Thursday. Therefore, Week1 is equivalent to the
first week that contains Jan 4, since Monday is considered to be the first
day of the week.
Note that WEEK_ISO() differs from the current definition
of WEEK(), which returns a value up to 54. For the WEEK() function, Week 1
is the week containing the first Saturday. This is equivalent to the week
containing Jan. 1, even if the week contains only one day.
DAYOFWEEK_ISO() 和 WEEK_ISO() 在版本 7 中创建的数据库中是自动提供的。如果数据库是在版本 7 之前创建的,则可能未提供这些函数。要使 DAYOFWEEK_ISO() 和 WEEK_ISO()
函数在这种数据库中可用,使用 db2updb 系统命令。有关 db2updb 的更多信息,参见《发行说明》中的“Command Reference”一节。
[ 页的顶部 | 上一页 | 下一页 | 目录 | 索引 ]