Loading column with time only format

Question

My DB , 11gR2 on OEL 5.5
Hi all
I have a problem with loading external table. I have txt file with column format HH24:MI:SS
START_TIME
00:10:20
01:15:11
02:11:10And I don't know wich data type use in external table because in future I will need to do some calculation on that column so I should load it as DATE, but I'm missing 'mm/dd/yy' at front. Any suggestion how to do it in right way ?

Answer 1

You could use a CHAR or DATE datatype for the external table, and do your math with this column properly.
The key is that converting a time string to a date datatype will add the current date to it. For example:
SQL> alter session set nls_date_format='dd/mm/yyyy hh24:mi:ss';
Session altered.
SQL> select to_date('00:10:20', 'hh24:mi:ss') from dual;
TO_DATE('00:10:20',
01/02/2011 00:10:20Here are sample code for both cases, using DATE and CHAR datatype. I have tested it on 11.2.0.1:
CREATE OR REPLACE DIRECTORY ext_tab_dir AS '/tmp';
-- /tmp/info.txt
1,00:10:20
2,01:15:11
3,02:11:10
alter session set nls_date_format='dd/mm/yyyy hh24:mi:ss';1) using DATE datatype
drop table tab_time_date;
CREATE TABLE tab_time_date (
  key VARCHAR2(5),
  start_time date)
  ORGANIZATION EXTERNAL (
     TYPE ORACLE_LOADER
     DEFAULT DIRECTORY ext_tab_dir
     ACCESS PARAMETERS
      (FIELDS TERMINATED BY ','
       (key char(5),
        start_time CHAR(8) DATE_FORMAT DATE MASK "HH24:MI:SS"
      LOCATION ('info.txt'));
select * from tab_time_date;
KEY   START_TIME
1     01/02/2011 00:10:20
2     01/02/2011 01:15:11
3     01/02/2011 02:11:102) using CHAR datatype
CREATE TABLE tab_time_char (
  key VARCHAR2(5),
  start_time char(8))
  ORGANIZATION EXTERNAL (
     TYPE ORACLE_LOADER
     DEFAULT DIRECTORY ext_tab_dir
     ACCESS PARAMETERS
      (FIELDS TERMINATED BY ','
      LOCATION ('info.txt'));
select key, to_date(start_time, 'hh24:mi:ss') from tab_time_char;
KEY   TO_DATE(START_TIME,
1     01/02/2011 00:10:20
2     01/02/2011 01:15:11
3     01/02/2011 02:11:10Regards.