I have two DATE column in table oracle database(12c).sysdate format is:
SQL> select sysdate from dual;
SYSDATE
---------
25-NOV-17
SQ>desc test_table
id NUMBER(10)
LAST_CREATED_DATE DATE
IS_CREATED_DATE DATE
where LAST_CREATED_DATE has different format to IS_CREATED_DATE(sysdate).
because LAST_CREATED_DATE is fixed and i'm reading from file(date format:20100330) where as IS_CREATED_DATE am inserting as sysdate(current date).
insert into test_table (id,LAST_CREATED_DATE,IS_CREATED_DATE) values (123,20100930,sysdate);
but with this insert statement am facing errors.
I tried ALTER SESSION SET NLS_DATE_FORMAT = 'yyyymmdd';.This works fine in current session,but looking for by which i can change ORACLE database date format to yyyymmdd(linux).
You should change your statement like this:
insert into test_table (id,LAST_CREATED_DATE,IS_CREATED_DATE)
values (123,to_date('20100930','yyyymmdd'),sysdate);
There are three ways to accomplish this task :
1)
SQL>conn myschema/mypwd
SQL>insert into test_table values(123,to_date('20100930','yyyymmdd'),sysdate);
2) as you mentioned
SQL>alter session set nls_date_format = 'yyyymmdd';
SQL>insert into test_table values(123,'20100930',sysdate); -- notice that 20100930 is quoted
3) globally(along with the db, needs restart, maybe dangerous on a production system in coordination with existing applications' date format model)
SQL>conn / as sysdba
SQL>alter system set nls_date_format = 'yyyymmdd' scope=spfile;
SQL>shutdown immediate;
SQL>startup;
SQL>conn myschema/mypwd
SQL>insert into test_table values(123,'20100930',sysdate); -- from now on, you don't need to alter your date parameter for every session
Related
DOB data type : DATE
13-JAN-76
10-FEB-80
17-MAR-79
---------------
Expected output
13-JAN-04
10-FEB-04
17-MAR-04
I tried use this but failed.
update table set dob=to_date(dob,'dd-MON-yyyy')||','||'2004','dd-MON-yyyy') where id='1001';
date format not recognized.
anyone help is much appreciated.
Here's one option:
(just to know date format; you don't have to do that)
SQL> alter session set nls_date_format = 'dd.mm.yyyy';
Session altered.
Here it goes:
SQL> select * from test;
DOB
----------
13.01.1976
10.02.1980
17.03.1979
SQL> update test set
2 dob = add_months(dob, (2004 - extract(year from dob)) * 12);
3 rows updated.
SQL> select * from test;
DOB
----------
13.01.2004
10.02.2004
17.03.2004
SQL>
You update statement relies on the session default date format. Typically this is defined by session parameter NLS_DATE_FORMAT
Better specify it explicitly:
update table set dob = to_date(2004 || TO_CHAR('dob', '-MM-DD'), 'YYYY-MM-DD')
In Oracle database I have this table (the data type of column col is DATE):
col
2021-02-26 23:14:24
Question: in my case, assuming over time DB settings haven't changed, which time zone does the table's column of DATE data type reflect?
UTC or
Europe/Helsinki?
Following I provide current DB settings.
Database time zone
SELECT DBTIMEZONE FROM DUAL;
|DBTIMEZONE |
|============|
|+00:00 |
Session time zone
SELECT SESSIONTIMEZONE FROM DUAL;
|SESSIONTIMEZONE|
|===============|
|Europe/Helsinki|
SELECT CURRENT_DATE FROM DUAL;
|CURRENT_DATE |
|===================|
|2021-07-18 15:05:32|
The time zone of database server's operating system
SELECT SYSDATE FROM DUAL;
|SYSDATE |
|===================|
|2021-07-18 15:05:32|
SELECT SYSTIMESTAMP FROM DUAL;
|SYSTIMESTAMP |
|==============================|
|2021-07-18 15:05:32.984 +03:00|
The time zone is undefined by the column.
You can do:
CREATE TABLE table_name (col DATE);
ALTER SESSION SET TIME_ZONE = 'UTC';
INSERT INTO table_name (col) VALUES (CURRENT_DATE);
ALTER SESSION SET TIME_ZONE = 'Europe/Helsinki';
INSERT INTO table_name (col) VALUES (CURRENT_DATE);
ALTER SESSION SET TIME_ZONE = 'America/New_York';
INSERT INTO table_name (col) VALUES (CURRENT_DATE);
Then:
ALTER SESSION SET NLS_DATE_FORMAT = 'YYYY-MM-DD HH24:MI:SS';
SELECT * FROM table_name;
Outputs:
COL
2021-07-18 21:06:05
2021-07-19 00:06:05
2021-07-18 17:06:05
db<>fiddle here
Those values were all inserted in the same second by the same user in the same session using identical SQL statements; however there is no consistency in the time zone of the DATE value as the session settings were altered between each statement; so you cannot rely on a DATE having any particular time zone.
If you want to work out what time zone your data is in then check your application that is storing the data:
Is it always using SYSDATE? Then the time zone of the column is the time zone of the database's system.
Does the application specify the time zone? Then the data will have the time zone specified by the application.
Is it taking data from an external source? Then check that external source.
Is it taking data from the user? Then you have no guarantees.
If the data is of type DATE, then it doesn't reflect any time zone at all. It's just a date and time, with time resolved to the second. SYSDATE simply gets date and time from the host server OS, so to the degree that the time portion is reflective of any time zone, it would be that of the host OS.
I'm creating tables in Oracle 11g table and came across one date field of format "YYYY-MM-DD".
I don't want to use varchar2 for this and when I use number(5), it's still accepting the input. Then what's the meaning of limit 5 here?
Please suggest me the best datatype I can use here.
This is, obviously, a date format mask. If you're about to store dates into that column, you should use the DATE datatype, such as
SQL> create table test
2 (datum date);
Table created.
Don't use VARCHAR2 (put strings into it, not dates) nor NUMBER (put numbers into it, not dates) datatypes for that. You'll regret it sooner than you think.
I'm going to enter some values into the table, showing different ways of how you could do that - it is important that you insert dates, not strings into it. Never rely on Oracle, implicitly converting strings you might provide to dates. Sooner or later, it'll produce an error.
SQL> insert into test values (date '2018-12-25');
1 row created.
SQL> insert into test values (to_date('09.05.2018', 'dd.mm.yyyy'));
1 row created.
SQL> insert into test values (sysdate);
1 row created.
Now, several ways of selecting that value:
This one returns date in a format currently set by my database's NLS settings:
SQL> select * from test;
DATUM
--------
25.12.18
09.05.18
09.05.18
I'm forcing it to return values in desired format, using ALTER SESSION:
SQL> alter session set nls_date_format = 'yyyy-mm-dd';
Session altered.
SQL> select * from test;
DATUM
----------
2018-12-25
2018-05-09
2018-05-09
Yet another format; note that value inserted via the SYSDATE function (which returns DATE) contains date and time component. It was "invisible" in previous examples:
SQL> alter session set nls_date_format = 'dd.mm.yyyy hh24:mi:ss';
Session altered.
SQL> select * from test;
DATUM
-------------------
25.12.2018 00:00:00
09.05.2018 00:00:00
09.05.2018 08:03:50
Using TO_CHAR function with some format (such as dd-mon-yyyy). I'm also requesting Oracle to "translate" month name into English (as my database works in Croatian):
SQL> select to_char(datum, 'dd-mon-yyyy', 'nls_date_language = english') datum from test;
DATUM
-----------
25-dec-2018
09-may-2018
09-may-2018
SQL>
[EDIT]
Oracle doesn't store DATE values in any "human" readable format (there's more to read on the Internet, Google for it). It is a format mask that represents that value to you.
I strongly suggest you NOT to store dates into any datatype column but DATE. It's a time bomb, waiting to explode (and then it'll hurt). Nobody stops you from entering a value as '1234-99-66' or '12-345-678'; what will you do with it, then?
Consider creating a view on a top of the table which uses TO_CHAR function and returns the value in a format you want ('yyyy-mm-dd'). DATE datatype column in a table makes sure that values are valid, and the view will let the third-party application to accept values it finds appropriate.
For example:
SQL> create view v_test as
2 select to_char(datum, 'yyyy-mm-dd') datum
3 from test;
View created.
SQL> select * from v_test;
DATUM
----------
2018-12-25
2018-05-09
2018-05-09
SQL>
So: you wouldn't let the third-party application to access the table, but the view instead.
I have a timestamp column in Oracle that has format 'MM/DD/YYYY HH24:MI.SxFF6'.
The data looks like below:
11/09/1917 10:45:28.230000
10/19/2014 18:09:28.410000
12/19/2011 11:06:28.340000
I need the timestamp to retain the value except for getting the milliseconds which need to be defaulted to 000000.
I tried query -
cast(to_char(Local_time, 'MM/DD/YYYY HH24:MI:SS') as timestamp(6))
But it is throwing error - "Not valid month"
Does anyone have any ideas on what I can try to get milliseconds to 0. I use Toad to query the table.
Your TIMESTAMP value does not have any format. All you have is a default display format - defined by current user NLS_TIMESTAMP_FORMAT setting.
Try this one:
CAST(Local_time AS TIMESTAMP(0))
If you like to trunc the milliseconds but haven them still available use
CAST(CAST(Local_time AS TIMESTAMP(0)) AS TIMESTAMP(6))
Something like this, perhaps?
SQL> create table test (col timestamp, result timestamp);
Table created.
SQL> insert into test (col) values (to_timestamp('11/09/1917 15:45:28.230000', 'MM/DD/YYYY HH24:MI:SS.FF6'));
1 row created.
SQL> update test set result = cast(col as date);
1 row updated.
SQL> select * From test;
COL RESULT
------------------------- -------------------------
09.11.17 15:45:28,230000 09.11.17 15:45:28,000000
SQL>
I am trying to insert date value as dd-mon-yy but the database is storing it as dd/mm/yy.
For example: INSERT INTO tablename VALUES (to_date('01-mar-09', 'dd-mon-yy');
The DB stores it as 01/03/09. Why is that? Whay can't I just store it as 01-mar-09?
Please help.
Date is a raw datatype. It doesn't have a format to be saved. It's upto you or the environment/session to decide how to display it.. use NLS_DATE_FORMAT parameter as required... using alter session or use to_char() function
alter session set nls_date_format = 'DD-MON-YY';
select sysdate from dual;
28-OCT-15
alter session set nls_date_format = 'MM/DD/YY';
select sysdate from dual;
10/28/15
The NLS parameters precedence is decided as below, if not set on session level then use instance level, if not set at instance level then use which is present at database level. Below are the views which provide set values at each level
NLS_SESSION_PARAMETERS => session level parameters
NLS_INSTANCE_PARAMETERS => instance level parameters
NLS_DATABASE_PARAMETERS => database level parameters
Oracle doesn't store a date as any format .. it just stores "a date". you are viewing it/displaying it as a different format. Check your nls_date settings.
SQL> select sysdate from dual;
SYSDATE
---------
28-OCT-15
SQL> alter session set nls_date_format='dd-mon-yyyy hh24:mi:ss'
Session altered.
SQL> select sysdate from dual;
SYSDATE
--------------------
28-oct-2015 11:00:56
SQL>