In Oracle :
My table has a timestamp column with time value of '02-NOV-11 12.00.00.000000000 AM' .
I tried to compare two dates:
select id from table1 where mytime = '02-NOV-11'
But it returns no records. Why?
Thanks!!!
I suspect it may be the default date format that is causing the problem, since the query works fine for me. It is not good practice to write queries that compare dates with strings, since this requires Oracle to format the string into a date using the default format, which may not be as you expect. It is better to use ANSI date literals like this:
select id from table1 where mytime = date '2011-11-02';
ANSI date literals must be in the format date 'yyyy-mm-dd', so there is no ambiguity about format.
A reference for datetime literals
Related
I have a column in a table that stores timestamp values as
"2018-01-12 16:13:51.107000000", i need to insert this column into a date column in another table, what format mask do i have to use here..
I have used the mask 'YYYY-MM-DD HH24:MI:SS.FF' but shows 'date format not recognized'.
I am assuming that you were trying to use TO_DATE on your text timestamp data. This won't work, because Oracle dates do not store anything more precise than seconds. Since your timestamps have fractional seconds, you may use TO_TIMESTAMP here, then cast that actual timestamp to a date:
SELECT
CAST(TO_TIMESTAMP('2018-01-12 16:13:51.100000',
'YYYY-MM-DD HH24:MI:SS.FF') AS DATE)
FROM dual;
12.01.2018 16:13:51
Demo
You can do this with a single call to TO_DATE(), but you must give the correct format model. Note that this solution is simpler (and possibly faster - if that matters) than converting to a timestamp and then casting to date.
If you want TO_DATE() to ignore part of the input string, you can use the "boilerplate text" syntax in the format model. That is enclosed in double quotes. For example, if your string included the letter T somewhere and it had to be ignored, you would include "T" in the same position in the format model.
This has some flexibility. In your case, you must ignore the decimal point, and up to nine decimal digits (the maximum for timestamp in Oracle). The format model will allow you to use ".999999999" (or any other digits, but 9999... is used by most programmers) to ignore a decimal point and UP TO nine digits after that.
Demo: (notice the double-quoted "boilerplate text" in the format model)
select to_date('2018-01-12 16:13:51.100000',
'YYYY-MM-DD HH24:MI:SS".999999999"') as dt
from dual;
DT
-------------------
2018-01-12 16:13:51
I have the following date which is in varchar2(11) column in database:
select valid_untill from SALES_ORDERS_V where header_id = 7999410;
30-May-2016
Using rtf template and xml source, the report output (PDF) is:
4950-11-19 04:45:49:0
I don't know its equal to "30-May-2016".
Why this is showing this, as I did not do any formating in rtf?
Not familiar with either RTF or XML-Publisher, but whenever you retrieve a date saved in string format, IF you use it as a date in your code and not as a string, you must make sure you retrieve it correctly.
In this case, with your select statement: it shouldn't be select valid-until from... (or is it really misspelled, with two l at the end: valid_until?) If it is meant to be used as a date, it should be
select to_date(valid_until, 'dd-Mon-yyyy') from ...
Really the problem here is that the date is stored as a string and not in the date datatype. Good luck!
I need your assistance with converting Oracle dates.
I have a column that stores dates like this 20150731 00:00:34.220. However, I would like to show the column like this 20150731 but when I run a simple select statement to test output I get the following error.
select TO_DATE('20150731 00:00:34.550','YYYYMMDD')
from dual
Error
ORA-01830: date format picture ends before converting entire input string
This query
select TO_DATE('20150731 00:00:34.550','YYYYMMDD')
from dual
leads to error
ORA-01830: date format picture ends before converting entire input string
because you pass string with length 22 characters, but at the same time you pass date format with 8 characters, which obviously doesn't correspond to string. You should write the query as
select to_timestamp('20150731 00:00:34.550','yyyymmdd hh24:mi:ss.ff3')
from dual
As for your table, since you have varchar2 column with dates, you have to take care about table content. Query requires exect matching of the source string and date format.
If you want to show only date without time and you don't need to process this string as date, you can make just
select substr('20150731 00:00:34.550', 1, 8)
from dual
What is the data type of the column? If it is DATE (as it should be) then not it is not stored in the format you say. It is stored in an internal binary format. You would/should use the to_char function to DISPLAY it in whatever format you choose. If you do not use the to_char function, it will be displayed in the format specified by NLS_DATE_FORMAT, which can be specified at several locations.
As for your example, you passed a string format of yyyymmd hh:mi:ss.fff', but you provided a description mask of only YYYYMMDD. It doesn't know what to do with time component. In addition to that when you SELECT TO_DATE, oracle also has to do an implied TO_CHAR to convert it back to a string for display purposes.
In addition, you provided your to_date with a character string that included fractions of seconds. A DATE data type only resolves to seconds. If you need fractional seconds, you need to use TIMESTAMP, not DATE.
If your column is a varchar and you need a date output:
select TO_DATE(substr('20150731 00:00:34.550', 1, 8),'YYYYMMDD') from dual
If it's in a date format and you need a string output:
select to_char(your_column, 'YYYYMMDD') from your_table
Is that being stored in an Oracle datetime column? If not, you may have to do some manipulation to get it into a DD-MON-YYYY format. If it is being stored as a text string you could use SUBSTR( Date_field, Start_Position, Length) to get the first 8 characters. check out this link SUBSTR
Working on the assumption that you're not trying to change the value in the column, and are just trying to show it in the YYYYMMDD format -
As mentioned by a_horse_with_no_name, you'll just need to convert it to a character string. In this example I used systimestamp as my date:
SELECT TO_CHAR(systimestamp,'YYYYMMDD') FROM DUAL
Result:
20160121
That should give you the YYYYMMDD format you want to display.
1) Why is that this doesn't works
select * from table where trunc(field1)=to_date('25-AUG-15','DD-MON-YY');
select * from table where trunc(field1)=to_date('25/Aug/15','DD/MON/YY');
row is returned in above cases.
So, does this mean that no matter what format the date is there in field1, if it is the valid date and matches with 25th August, it will be returned ( it won't care what format specifier we specify at the right side of the query i.e. DD-MON-YY or DD/MON/YY or anything else) ?
2) but comparsion as string exactly works:
select * from table where to_char(field1)=to_char(to_date
('25/AUG/15','DD/MON/YY'), 'DD/MON/YY');
no row is returned as the comparison is performed exactly.
I have field1 as '25-AUG-15' ( although it can be viewed differently doing alter session NLS_DATE_FORMAT...)
field1 is of DATE type
Any help in understanding this is appreciated specifically with respect to point 1
The DATE data type does not have format -- it's simply a number. So, a DATE 25-Aug-2015 is the same as DATE 25/AUG/15, as well as DATE 2015-08-15, because it's the same DATE.
Strings, on the other hand, are collections of characters, so '25-Aug-2015' is obviously different from '25/AUG/15'.
In the first example you are comparing DATE values. In the second example you are comparing strings.
So you have a field of type DATE with value of The 25th of August 2015,
but it could be visualized in different ways, what in fact is named format.
The DATE has format!
The DATE has implicit format defined by Oracle, in your case it is DD-MON-YY, because you see your field as 25-AUG-15.
You can select your data without TO_DATE conversion, just matching this default format like this:
select * from table where trunc(field1)='25-AUG-15';
In fact, it's not recommended, because if someone will change the default format, Oracle will not be able to understand that you are going to tell him a DATE.
So the to_date conversion in this case:
select * from table where
trunc(field1)=to_date('25/AUG/15','DD/MON/YY');
is used to specify that you wanna tell to Oracle a DATE type with value of 25th of August 2015, using a diffrent format, specified as second parameter. (DD/MM/YY in this case).
I have created a table in Oracle in which I have KPI_START_DATE column which is a Date datatype, and KPI_START_TIME which is a TIMESTAMP datatype.
Now I want to modify this date dataype for
KPI_START_DATE to dd/mm/yyyy
and
KPI_START_TIME to HH:MI:SS.
So that user should always enter the date and time in this column in this proper format.
I tried below query but its was giving error:
Alter table KPI_DEFINITION MODIFY(to_char(KPI_START_DATE,'dd/mm/yyyy') )
DATE and TIMESTAMP columns do not have any inherent readable format. The values are stored in Oracle's own internal representation, which has no resemblance to a human-readable date or time. At the point to retrieve or display a value you can convert it to whatever format you want, with to_char().
Both DATE and TIMESTAMP have date and time components (to second precision with DATE, and with fractional seconds with TIMESTAMP; plus time zone information with the extended data types), and you should not try to store them separately as two columns. Have a single column and extract the information you need at any time; to get the information out of a single column but split into two fields you could do:
select to_char(KPI_START, 'dd/mm/yyyy') as KPI_START_DATE,
to_char(KPI_START, 'hh24:mi:ss') as KPI_START_TIME
but you'd generally want both together anyway:
select to_char(KPI_START, 'dd/mm/yyyy hh24:mi:ss')
Also notice the 'hh24' format model to get the 24-hour clock time; otherwise you wouldn't see any difference between 3 a.m. and 3 p.m.
You can store a value in either type of column with the time set to midnight, but it does still have a time component - it is just midnight. You can't store a value in either type of column with just a time component - it has to have a date too. You could make that a nominal date and just ignore it, but I've never seen a valid reason to do that - you're wasting storage in two columns, and making searching for and comparing values much harder. Oracle even provides a default date if you don't specify one (first day of current month). But the value always has both a date and a time part:
create table KPI_DEFINITION (KPI_START date);
insert into KPI_DEFINITION (KPI_START)
values (to_date('27/01/2015', 'DD/MM/YYYY'));
insert into KPI_DEFINITION (KPI_START)
values (to_date('12:41:57', 'HH24:MI:SS'));
select to_char(KPI_START, 'YYYY-MM-DD HH24:MI:SS') from KPI_DEFINITION;
TO_CHAR(KPI_START,'YYYY-MM-DDHH24:MI:SS')
-----------------------------------------
2015-01-27 00:00:00
2015-01-01 12:41:57
Your users should be inserting a single value with both date and time as one:
insert into KPI_DEFINITION (KPI_START)
values (to_date('27/01/2015 12:41:57', 'DD/MM/YYYY HH24:MI:SS'));
select to_char(KPI_START, 'YYYY-MM-DD HH24:MI:SS') from KPI_DEFINITION;
TO_CHAR(KPI_START,'YYYY-MM-DDHH24:MI:SS')
-----------------------------------------
2015-01-27 12:41:57
You can also use date or timestamp literals, and if using to_date() you should always specify the full format - don't rely on NLS settings as they may be different for other users.
You should understand difference between datatype and format. DATE is a datatype. TIMESTAMP is a datatype. None of them have formats, they're just numbers.
When converting character datatype to or from date datatype, format should be applied. It's an attribute of an actual conversion, nothing else.
Look at this:
SQL> create table tmp$date(d date);
Table created
SQL> insert into tmp$date values (DATE '2010-11-01');
1 row inserted
SQL> insert into tmp$date values (DATE '2014-12-28');
1 row inserted
SQL> select d, dump(d) from tmp$date;
D DUMP(D)
----------- ---------------------------------
01.11.2010 Typ=12 Len=7: 120,110,11,1,1,1,1
28.12.2014 Typ=12 Len=7: 120,114,12,28,1,1,1
There is no any 'format' here.
DISPLAYING and STORING are NOT the same when it comes to DATE.
When people say Oracle isn’t storing the date in the format they wanted, what is really happening is Oracle is not presenting the date in the character string format they expected or wanted.
When a data element of type DATE is selected, it must be converted from its internal, binary format, to a string of characters for human consumption. The conversion of data from one type to another is known as known a “conversion”, “type casting” or “coercion”. In Oracle the conversion between dates and character strings is controlled by the NLS_DATE_FORMAT model. The NLS_DATE_FORMAT can be set in any of several different locations, each with its own scope of influence.
I could go on with my leacture over DATE data type, but I am glad that someone has already got a good writeup over this. Please read this https://edstevensdba.wordpress.com/2011/04/07/nls_date_format/