Oracle: removing time from datetime field - sql

Given a TIMESTAMP(4) column, what is the correct way to select only the date and ignore the time.
For example, a select on a timestamp field containing
22:07:2015:17:55:07
would return
22:07:2015:00:00:00
Thanks

select to_char(trunc(systimestamp),'yyyy-mm-dd hh24:mi:ss') from dual;

Related

How to trim milliseconds of a timestamp field in oracle

I have a table EMPLOYEE and it has two TIMESTAMP fields "CRTE_DTM" and "END_DTM".
I would like to create a view on top EMPLOYEE table where I can put some function on these two fields to return TIMESTAMP with only 3 precision of milliseconds.
Example:
If I have below row in EMPLOYEE table
CRTE_DTM
----------------
10-SEP-02 02.10.10.123000000 PM
I would like to trim the timestamp to have only 3 precision in milliseconds, see below,
CRTE_DTM
----------------
10-SEP-02 02.10.10.123 PM
Note: I'm using this view to load data into a table where "CRTE_DTM" and "END_DTM" fields are TIMESTAMP's
If you can recreate the table (or add columns, copy data, drop the old and rename) you can use the datatype TIMESTAMP(3). The default for TIMESTAMP is 6 fractional digits, but it can be overridden.
Alternatively you can convert to a string with a specified format and (optionally if you want to work with TIMESTAMP) back again:
select to_timestamp(
to_char(crte_dtm, 'YYYY-MM-DD HH24:MI:SS.FF3'),
'YYYY-MM-DD HH24:MI:SS.FF3') from employee;
You might try the following:
CREATE VIEW myview AS
SELECT <other_columns>
, CAST(crte_dtm AS TIMESTAMP(3)) AS crte_dtm
, CAST(end_dtm AS TIMESTAMP(3)) AS end_dtm
FROM employee;
Hope this helps.
10-SEP-02 02.10.10.123000000 PM is the same timestamp as 10-SEP-02 02.10.10.123 PM. What you can do is select a string showing this timestamp in the desired format:
select to_char(timestamp_column, 'dd-MON-yy hh24.mi.ss.ff3', 'nls_date_language=english')
from mytable;
select localtimestamp(9) from dual;

Timestamp to date convertion in oracle sql [duplicate]

How can we convert timestamp to date?
The table has a field, start_ts which is of the timestamp format:
'05/13/2016 4:58:11.123456 PM'
I need to query the table and find the maximum and min timestamp in the table but I'm not able to.
Select max(start_ts)
from db
where cast(start_ts as date) = '13-may-2016'
But the query is not returning any values.
Please help me in finding the max timestamp for a date.
CAST(timestamp_expression AS DATE)
For example, The query is : SELECT CAST(SYSTIMESTAMP AS DATE) FROM dual;
Try using TRUNC and TO_DATE instead
WHERE
TRUNC(start_ts) = TO_DATE('2016-05-13', 'YYYY-MM-DD')
Alternatively, you can use >= and < instead to avoid use of function in the start_ts column:
WHERE
start_ts >= TO_DATE('2016-05-13', 'YYYY-MM-DD')
AND start_ts < TO_DATE('2016-05-14', 'YYYY-MM-DD')
Format like this while selecting:
to_char(systimestamp, 'DD-MON-YYYY')
Eg:
select to_char(systimestamp, 'DD-MON-YYYY') from dual;
If the datatype is timestamp then the visible format is irrelevant.
You should avoid converting the data to date or use of to_char. Instead compare the timestamp data to timestamp values using TO_TIMESTAMP()
WHERE start_ts >= TO_TIMESTAMP('2016-05-13', 'YYYY-MM-DD')
AND start_ts < TO_TIMESTAMP('2016-05-14', 'YYYY-MM-DD')
You can try the simple one
select to_date('2020-07-08T15:30:42Z','yyyy-mm-dd"T"hh24:mi:ss"Z"') from dual;
You can use:
select to_date(to_char(date_field,'dd/mm/yyyy')) from table
I'd go with the following:
Select max(start_ts)
from db
where trunc(start_ts) = date'13-may-2016'
If you have milliseconds in the date string, you can use the following.
select TO_TIMESTAMP(SUBSTR('2020-09-10T09:37:28.378-07:00',1,23), 'YYYY-MM-DD"T"HH24:MI:SS:FF3')From Dual;
And then convert it to Date with:
select trunc(TO_TIMESTAMP(SUBSTR('2020-09-10T09:37:28.378-07:00',1,23), 'YYYY-MM-DD"T"HH24:MI:SS:FF3')) From Dual;
It worked for me, hope it will help you as well.
This may not be the correct way to do it. But I have solved the problem using substring function.
Select max(start_ts), min(start_ts)from db where SUBSTR(start_ts, 0,9) ='13-may-2016'
using this I was able to retrieve the max and min timestamp.

YYYYMMDD to YYYYMM in oracle

I have a column with DATE datatype in a table.
I am trying to retrieve the column values in YYYYMM format. My select query looks like below
select *
from tablename
where date column = to_char(to_date('12/31/4000','MM/DD/YYYY'),'YYYYMM');
I am getting below exception.
ORA-01847: day of month must be between 1 and last day of month
Appreciate any input on this.
I think the simplest method is:
where to_char(datecolumn, 'YYYYMM') = '400012'
Or, if you prefer:
where to_char(datecolumn, 'YYYYMM') = to_char(to_date('12/31/4000', 'MM/DD/YYYY'), 'YYYYMM');
Syntax-wise, the right hand date (to the right of the equals) is OK. But you are doing a character comparison, not a date comparison.
This works for me in multiple databases:
select to_char (to_date('12/31/4000','MM/DD/YYYY'),'YYYYMM')
from dual;
Even though your column is named DATE_COLUMN, you are comparing based on characters in the query.
So, try this instead - this compares based on dates (NOT a character comparison) and truncates off the hour, minute, ETC. so you are only comparing the DAY:
select * from DATE_TAB
where TRUNC(DATE1, 'DDD') = TRUNC(to_date('12/31/4000','MM/DD/YYYY'),'DDD');
NOTE: The DATE1 field above is a DATE field. If you're DATE_COLUMN is not a DATE field, you must
convert it to a DATE datatype first (using TO_DATE, ETC.)
Assuming that "date_column" is actually a date, and that you have an index on date_column, you can do something like this to return the data quickly (without truncating dates in all rows to do a comparison):
with dat as (
select level as id, sysdate - (level*10) as date_column
from dual
connect by level <= 100
)
select id, date_column
from dat
where date_column between to_date('11/1/2013', 'MM/DD/YYYY') and last_day(to_date('11/2013 23:59:59', 'MM/YYYY HH24:MI:SS'))
Here I just dummy up some data with dates going back a few years. This example picks all rows that have a date in the month of November 2013.
If your date_column's data-type is DATE, then use
select *
from tablename
where TO_CHAR(date_column,'YYYYMM') = to_char (to_date('12/31/4000','MM/DD/YYYY'),'YYYYMM');
If your date_column's data-type is VARCHAR, then use:
select *
from tablename
where date_column = to_char (to_date('12/31/4000','MM/DD/YYYY'),'YYYYMM');
I somehow feel your error is because you have a space between date and column as
"date column". If the field name in the table is "COLUMN", then just removing the word "DATE" from your original query would suffice, as:
select *
from tablename
where column = to_char(to_date('12/31/4000','MM/DD/YYYY'),'YYYYMM');
If your column (YYYYMMDD) is in number format, the simplest way to get YYYYMM would be
select floor(DATE/100)
from tablename;

store dates in oracle

I have a table as
create table Dummy (date_created date)
in oracle.I want to store date in 'dd-mon-yyyy' (12-dec-2010) format.
How should i do this.
Please help.
In Oracle a column created with the DATE datatype just stores the date. It doesn't have a particular format, it just stores the day, month, year, hour, minute, and second. You need to convert from whatever format you have using the TO_DATE function. If you have a text string with the date in 'dd-mon-yyyy' format and you want to put this date into your table you'd use something like
INSERT INTO DUMMY (DATE_CREATED)
VALUES (TO_DATE('01-FEB-2011', 'DD-MON-YYYY');
Going the other way (from DATE column value to character string) you'd use the TO_CHAR function. If you were retrieving a value from your table and wanted to convert it to 'DD-MON-YYYY' format you'd use something like
SELECT TO_CHAR(DATE_CREATED, 'DD-MON-YYYY')
FROM DUMMY;
Share and enjoy.
Use to_date() function. In your case, the syntax would be
insert into Dummy values (to_date('08-09-2010', 'dd-mm-yyyy'));
Here is a link to the detailed help.
The DATE datatype will store date and time information (century, year, month, day, hours, minutes, and seconds) in an internal format in the database. When you get it out of the database, you can choose to display it in whatever format you like.
This information is either created using implicit conversion from a string or explicitly using either the TO_DATE function or the ANSI date literal. If you look in the v$nls_parameters view, this will tell you what the NLS_DATE_FORMAT is which is generally used for the implicit conversion. This may often be defined as DD-MON-RR, which might be why the date will come out as 23-DEC-10 when the query select sysdate from dual is run. (Not entirely sure I'm right about the nls stuff. Correct me if I'm wrong.)
However, all the date information is available if you know how to get it. The query select to_char(sysdate, 'dd-mon-yyyy hh24:mi:ss') from dual will return all the date fields.
Likewise, the insert statement shown below will create a row with a date value in it.
insert into dummy (date_created)
values (to_date('12-dec-2010 12:34:56', 'dd-mon-yyyy hh24:mi:ss'))`
This data can then be retrieved.
select date_created from dummy
This will implicitly convert the date to a character string using the NLS_DATE_FORMAT, providing the output below.
DATE_CREA
---------
23-DEC-10
The full date information is available by explicitly converting the date to a character string.
select to_char(date_created, 'DD-MON-YYYY') as date_created from dummy;
select to_char(date_created, 'DD-MON-YYYY HH24:MI:SS') as date_created
from dummy;
This will provide output in the format you require:
DATE_CREATE
-----------
23-DEC-2010
If you always use the TO_DATE and TO_CHAR functions to convert to/from a date datatype, then you will have fewer problems. Implicit conversion is useful but can cause some confusion or problems.
You can keep and eye here
http://www.techonthenet.com/oracle/functions/to_date.php
use to_date function to save a data with the format you need. I suggest to use SYSDATE updating table and when you need to read data from table use something like that:
dbms_output.put_line(TO_CHAR(SYSDATE, 'DD-MON-YYYY HH24:MI:SS'));
to solve your problem use:
to_date('08/JAN/2010', 'DD/MON/YYYY')
Just use TRUNC(YourDate) if date have time part, it will be truncate time part. Oracle have not just 'DATE' type, 'DATE' always have time part.
However if you do not specify time - it will 00:00:00.
SELECT TRUNC(SYSDATE) from dual
Result:
23-12-2010
Oracle does not support DATE without time part.
You can make it always be an integer date by adding a CHECK constraint:
CREATE TABLE dummy (date_created date CHECK (date_created = TRUNC(date_created)))
, insert it in any format you want:
INSERT
INTO dummy (date_created)
VALUES (TO_DATE('23-DEC-2010', 'dd-mon-yyyy'))
and select it in any format you want:
SELECT TO_CHAR(date_created, 'dd-mon-yyyy')
FROM dummy

Select from table by knowing only date without time (ORACLE)

I'm trying to retrieve records from table by knowing the date in column contains date and time.
Suppose I have table called t1 which contains only two column name and date respectively.
The data stored in column date like this 8/3/2010 12:34:20 PM.
I want to retrieve this record by this query for example (note I don't put the time):
Select * From t1 Where date="8/3/2010"
This query give me nothing !
How can I retrieve date by knowing only date without the time?
DATE is a reserved keyword in Oracle, so I'm using column-name your_date instead.
If you have an index on your_date, I would use
WHERE your_date >= TO_DATE('2010-08-03', 'YYYY-MM-DD')
AND your_date < TO_DATE('2010-08-04', 'YYYY-MM-DD')
or BETWEEN:
WHERE your_date BETWEEN TO_DATE('2010-08-03', 'YYYY-MM-DD')
AND TO_DATE('2010-08-03 23:59:59', 'YYYY-MM-DD HH24:MI:SS')
If there is no index or if there are not too many records
WHERE TRUNC(your_date) = TO_DATE('2010-08-03', 'YYYY-MM-DD')
should be sufficient. TRUNC without parameter removes hours, minutes and seconds from a DATE.
If performance really matters, consider putting a Function Based Index on that column:
CREATE INDEX trunc_date_idx ON t1(TRUNC(your_date));
Personally, I usually go with:
select *
from t1
where date between trunc( :somedate ) -- 00:00:00
and trunc( :somedate ) + .99999 -- 23:59:59
Convert your date column to the correct format and compare:
SELECT * From my_table WHERE to_char(my_table.my_date_col,'MM/dd/yyyy') = '8/3/2010'
This part
to_char(my_table.my_date_col,'MM/dd/yyyy')
Will result in string '8/3/2010'
You could use the between function to get all records between 2010-08-03 00:00:00:000 AND 2010-08-03 23:59:59:000
trunc(my_date,'DD') will give you just the date and not the time in Oracle.
Simply use this one:
select * from t1 where to_date(date_column)='8/3/2010'
Try the following way.
Select * from t1 where date(col_name)="8/3/2010"