1.trunc函数 1).trunc(date) 格式:trunc(date,fmt) trunc用于截取时间,即便你指定不同的格式类型,返回的类型始终都是时间类型. 示例: with dates as ( select date'2015-01-01' d from dual union select date'2015-01-10' d from dual union select date'2015-02-01' d from dual union select timestamp'201…