I have a table with date type column.
I am trying to insert date in it:
But I get an error:
Please give me to make the correct query to put the date
Easy fix::
INSERT INTO t(dob) VALUES(DATE '2015-12-17');
Assuming this is an Oracle question based on the ORA-01843 error message, the problem appears to be in the date formatting as the error suggests.
In the provided example does the date '6-3-2012' mean '3 March 2012' or 'June 6, 2012?' The answer lies within the NLS_DATE_FORMAT parameter.
Out of the box, the Oracle date format is DD-MON-RR. So your corrected date format is either '03-MAR-12' or '06-JUN-12.' If the NLS_DATE_FORMAT has not been changed.
Never try to insert a string into a date column! If you have a string, use the to_date function with an explicit date format (and use 4 digit dates).
Relying on nls_date_format to implicitly convert your strings is just asking for trouble (like you just did), it can very easily change, even some apps will change it themselves.
The date literal (date '2015-12-17' https://docs.oracle.com/cd/B19306_01/server.102/b14200/sql_elements003.htm#BABGIGCJ) always uses the same date format so that might be okay for ad hoc statements but you need to be aware that it is literal by name and literal by nature. They don't support bind variables so you will end up writing unshareable SQL to chew up your shared pool.
Related
When I execute this in PL/SQL Developer :
SELECT to_date('29/03/17 14:05','DD/MM/RR HH24:MI') FROM dual;
Here's what I get :
3/29/2017 2:05:00 PM
How is this possible ? I use HH24 but it seems like it's HH that's being used instead. The day and month are also not in the format I entered.
What you are doing with the to_date method is parsing the string into a date object. If you then want to output the date object as string with a different format you should use the to_char method.
Example:
SELECT to_char(
to_date('29/03/17 14:05','DD/MM/RR HH24:MI'),
'DD/MM/RR HH24:MI'
) FROM dual;
Ok, conceptual excercise coming up
Which of these dates represents the 1st January 2017?
01/01/2017
2017-01-01
01-JAN-2017
That's right, all of them. The date datatype is not a format, it stores the value of the date, not how it appears.
If using Oracle, adjust your NLS_DATE_FORMAT to match your expectation, but again, this is just how the system will display the date, not how it stores it.
(N.B. This answer is more to give more clarity to the other answers but it's too long for a comment.)
Oracle stores DATEs (and TIMESTAMPs etc) in its own specific format. Us humans represent dates in a variety of different formats and we deal with strings. Even us humans can get confused over what a date string represents, given no context - e.g. 03/09/2017 - is that the 3rd of September, 2017 or the 9th of March 2017?
So, when you pass a date into Oracle, you need to convert it into Oracle's date format by passing a string in and telling Oracle what the date format of that string is. This can be done using to_date() or via the DATE literal (which is always in yyyy-mm-dd format).
Conversely, when you want to read something that's stored in Oracle's DATE datatype, you need to tell Oracle how you want it to be displayed, which you can do by using to_char() with the appropriate format mask.
If you fail to explicitly convert the string-to-a-date or date-to-a-string, then Oracle uses the format specified in the NLS_DATE_FORMAT to decide how to do the conversion.
In your case, you didn't specify how you wanted your date to be displayed, so Oracle has to use to_char() along with the format contained in your NLS_DATE_FORMAT in order to display the date as a string, and clearly that's different to the format you passed the date-string in as.
I have a question regarding SQL dates.
The table I am working with has a date field in the following format: "22-SEP-08". The field is a date column.
I am trying to figure out how to output records from 1/1/2000 to present day.
The code below is not filtering the date field:
Select distinct entity.lt_date
from feed.entitytable entity
where entity.lt_date >= '2000-01-01'
Any help regarding this issue is much appreciated. Thanks!
Edit: I am using Oracle SQL Developer to write my code.
DATEs do not have "a format". Any format you see is applied by the application displaying the date value.
You can either change the configuration of SQL Developer to display dates in a different format, or you can use to_char() to format the date the way you want.
The reason your statement does not work, is most probably because of the implicit data type conversion that you are relying on.
'2000-01-01' is a string value, not a date. And the string is converted using the NLS settings of your session. Given the fact that you see dates displayed as DD-MON-YY means that that is the format that is used by the evil implicit data type conversion. You should supply date values always as real date literals.
There are two ways of specifying a real date literal. The first is ANSI SQL and simple uses the keyword DATE in front of an ISO formatted string:
where entity.lt_date >= DATE '2000-01-01'
Note the DATE keyword in front of the string, wich makes it a real date literal not a string expression.
The other option is to use to_date() to convert a character value into a date:
where entity.lt_date >= to_date('2000-01-01', 'yyyy-mm-dd');
More details about specifying date literals can be found in the manual:
Date literals
to_date function
My guess is the data type isn't a Date. Just in case its a char type, try to convert it using the Oracle TO_DATE() function. The Oracle documentation below should help you with parameters.
http://docs.oracle.com/cd/B19306_01/server.102/b14200/functions183.htm
An implicit datatype conversion bites once again.
You're right. The predicate is not doing the comparison you are expecting,
Oracle is performing an implicit datatype conversion, from DATE to VARCHAR, so that it can do a comparison to the string literal.
If lt_date column is DATE datatype, then Oracle is seeing your where clause:
where entity.lt_date >= '2000-01-01'
Oracle is actually seeing it as if it's written like this:
where TO_CHAR(entity.lt_date) >= '2000-01-01'
And that's where the "format" problem comes in. The column itself does not have a "format". Because the second argument to the TO_CHAR function is not supplied, Oracle is using the value of the NLS_DATE_FORMAT parameter (from your session). And that's probably set to DD-MON-YY. Which is why that's the "format" you're seeing when you a run a SELECT statement in SQL*Plus. Because the DATE value is (again) being run through a TO_CHAR function to get a string that can be displayed.
To get the "filtering" you want, don't do a comparison to a string literal. Instead, do the comparison to an expression that has DATE datatype.
You can use the Oracle TO_DATE function. And you don't want to rely on setting of NLS_DATE_FORMAT, explicitly specify the format model as the second argument to the function. For example:
DO THIS
where entity.lt_date >= TO_DATE('2000-01-01','YYYY-MM-DD')
DON'T DO THIS
It's also possible to specify the format model as the second argument to the TO_CHAR function.
where TO_CHAR(entity.lt_date,'YYYY-MM-DD') >= '2001-01-01'
But you don't want to do that because that's going to force Oracle to evaluate that expression on the left side for every flipping row in the table, so it has a string value to do the comparison. (That's true unless someone created a function-based index for you.) If you do the comparison on the bare column, using the TO_DATE on the literal side, Oracle can make effective use of an appropriate index (with lt_date as the leading column) to satisfy the predicate.
I am a newbie for Oracle database programming and I wish to INSERT date (also display) in 'DD MON YYYY' format. (PS: This only involves INSERT event). Which data type (DATE or TIMESTAMP) is the most suitable option for me in order to accomplish this format? How was I supposed to do that? Thanks.
A DATE column does not have any format.
So the format that you use when inserting or updating data is irrelevant for displaying that data (that's one of the reasons why you should never store a date in a VARCHAR column).
Any formatted output you see for a DATE column in your SQL tool (e.g. SQL*Plus) is applied by that tool. It is not part of the data stored in that column.
When providing a date literal you should either use the to_date() function with an explicit format mask:
insert into some_table (some_date_column)
values (to_date('27-06-2014', 'dd-mm-yyyy'));
I also do not recommend using formats with written month names (27-JUN-2014) when supplying a date literal because they also depend on the NLS settings of the client computer and might produce (random) errors due to different languages. Using numbers only is much more robust.
I prefer to use ANSI date literals because it's a bit less typing:
insert into some_table (some_date_column)
values (DATE '2014-06-27');
The format for an ANSI date (or timestamp) literal is always the ISO format (yyyy-mm-dd).
When you select your data you can display the date in whatever format you like. Either by using the to_char() function (e.g. when using a SQL tool) or using functions from your programming language (the preferred way to use inside an application):
select to_char(some_date_column,'dd-mon-yyyy')
from some_table;
Note that the DATE data type in Oracle (despite it's name) also stores the time. a TIMESTAMP does the same thing only with a higher precision (it includes milliseconds, whereas the DATE data type only stores seconds).
To insert a record,
INSERT INTO TABLE_NAME (DATE_FIELD) VALUES (TO_DATE ('27-JUN-2014', 'DD-MON-YYYY');
It is advisable to use DATE data-type until and unless you need the date's accuracy to be till milli seconds. In your case, go with DATE datatype and TIMESTAMP is not necessary
To select a record,
SELECT TO_CHAR(DATE_FIELD, 'DD-MON-YYYY') FROM TABLE_NAME;
In genral, remember this:
TO_DATE is a function used to convert a string(CHAR) TO DATE
TO_CHAR is a function used to convert a DATE to a string(CHAR)
In this scenario date datatype will be suitable for you, and for the desired format you should try like this:-
INSERT INTO TABLE_NAME(DATE_COLUMN) VALUES('27-JUN-2014');
Hope this can help you.
I want to create a table in Oracle 10g and I want to specify the date format for my date column. If I use the below syntax:
create table datetest(
........
startdate date);
Then the date column will accept the date format DD-MON-YY which I dont want.
I want the syntax for my date column to be MM-DD-YYYY
Please let me know how to proceed with this.
Regards,
A DATE has no inherent format. It is not simply a string that happens to represent a date. Oracle has its own internal format for storing date values.
Formats come into play when actual date values need to be converted into strings or vice versa, which of course happens a lot since interactively we write dates out as strings.
The default date format for your database is determined by the settings NLS_DATE_FORMAT, which you probably have set to DD-MON-YYYY (which I believe is the default setting for American English locales). You can change this at the database level or for a single session for convenience, but in general it is safer programming practice to be explicit so that you don't get errors or, worse, wrong results if your code is run in a different environment.
The simplest way to specify a date value unambiguously is a date literal, which is the word 'date' followed by a string representing the date in YYYY-MM-DD format, e.g. date '2012-11-13'. The Oracle parser directly translates this into the corresponding internal date value.
If you want to use a different format, then I recommend explicitly using TO_CHAR/TO_DATE with your desired format model in your code. Examples:
INSERT INTO my_table (my_date) VALUES ( TO_DATE( '11-13-2012', 'MM-DD-YYYY' ) );
SELECT TO_CHAR( my_date, 'MM-DD-YYYY' ) FROM my_table;
dates rdo not have a format like you're suggesting. they are stored internally as a 7 byte number. to format the date when selecting, please use TO_CHAR(yourdatefield, 'format')
where formats are all shown here: http://docs.oracle.com/cd/B19306_01/server.102/b14200/sql_elements004.htm#i34924
eg to_char(startdate, 'mm-dd-yyyy')
There must be a very simple answer, but I can't find it anywhere.
I have the following which is a section of my select statement:
case when q.renewal_date is not null then
to_date(q._renewal_date, 'DD/MM/YYYY')
else
to_date(w.END_DATE, 'DD/MM/YYYY')
end END_DATE,
according to all of the docs I can find the MM should give the month in numbers however I'm getting results such as:
30-SEP-12
26-JUN-11
30-SEP-12
It's also interesting that they're hyphenated (-) and not with slashes (/).
So what's the reason for this and how do I achieve what I want?
Assuming w.end_Date and q._renewal_date are actual dates, you want to to_char them, not to_date. At present I would say you are seeing the dates in the format specified by your NLS settings. (If they are not dates, you are converting them to dates, but still letting your NLS settings choose the format you view it in)
As you are TO_DATEing the value it is stored by Oracle internally as a date. It is displayed back to you using your NLS_DATE settings value which i would assume are set to DD-MON-YY by default.
You can check with
SELECT *
FROM v$parameter
WHERE name = 'nls_date_format';
You'll need to either alter your NLS_DATE_FORMAT setting (either for your session or for the DB) or TO_CHAR the output to the format you want to see.
to_date converts a string to a date. The code you have is taking a string (q._renewal_date) in 'DD/MM/YYYY' format and converting it to a date. What you are seeing is the default rendering of the date field.
Depending on what type q._renewal_date is, you probably need to use a different conversion/formatting function.