Oracle TIMESTAMP(3)类型使用

SQL> desc err_info
 Name					   Null?    Type
 ----------------------------------------- -------- ----------------------------
 USER_ID					    VARCHAR2(20)
 HOST_IP					    VARCHAR2(20)
 SDATE						    TIMESTAMP(3)
 ERR_INFO					    VARCHAR2(1000)

SQL> select count(*) from err_info; 

  COUNT(*)
----------
	 4


SQL> select count(*) from err_info where  sdate=to_date('2015-05-27','yyyy-mm-dd');

  COUNT(*)
----------
	 0

SQL> select count(*)  from err_info where  sdate between to_date('201505271500','YYYYMMDDHH24MI') and  to_date('201505271600','YYYYMMDDHH24MI') ;

  COUNT(*)
----------
	 4