EXTRACT the date and time - (Teradata) - sql

I am trying to extract the date and time from a field in Teradata.
The field in question is:
VwNIMEventFct.EVENT_GMT_TIMESTAMP
Here is what the data look like:
01/02/2012 12:18:59.306000
I'd like the date and time only.
I have tried using EXTRACT(Date, EXTRACT(DAY_HOUR and a few others with no success.
DATE_FORMAT() does not appear to work since I'm on Teradata.
How would I select the date and time from VwNIMEventFct.EVENT_GMT_TIMESTAMP?

If the datatype of EVENT_GMT_TIMESTAMP is a TIMESTAMP, it's simple Standard SQL:
CAST(EVENT_GMT_TIMESTAMP AS DATE)
CAST(EVENT_GMT_TIMESTAMP AS TIME)
If it's a CHAR you need to apply a FORMAT, too:
CAST(CAST(EVENT_GMT_TIMESTAMP AS TIMESTAMP FORMAT 'dd/mm/yyyyBhh:mi:SS.s(6)') AS DATE)
CAST(CAST(EVENT_GMT_TIMESTAMP AS TIMESTAMP FORMAT 'dd/mm/yyyyBhh:mi:SS.s(6)') AS TIME)
Edit:
For simply changing the display format you need to add a FORMAT and a CAST to a string:
CAST(CAST(EVENT_GMT_TIMESTAMP AS FORMAT 'YYYYMMDDHHMI') AS CHAR(12))
or
CAST(CAST(EVENT_GMT_TIMESTAMP AS FORMAT 'YYYYMMDDHHMISS') AS CHAR(14))
If you don't care about display, just want to truncate the seconds:
EVENT_GMT_TIMESTAMP - (EXTRACT(SECOND FROM EVENT_GMT_TIMESTAMP) * INTERVAL '1.000000' SECOND)
Working with timestamps is a bit tricky :-)

I know this is an old topic, but I've struggled with this too. Try:
CAST(EVENT_GMT_TIMESTAMP AS TIMESTAMP(0))
The result will be
01/02/2012 12:18:59
The datatype will still be timestamp, but it will just be the date and time with no microseconds (looks just like a datetime object in Microsoft SQL).

Related

Using the To_Date function is not converting to the expected format

I'm trying to convert a char (output from a substr operation) into a dateTime format using TO_DATE with the following format - hh24:mi:ss.
The output of the substr looks fine but as soon as I run it through the TO_DATE function it converts every row for this column into 01-MAR-22.
To demonstrate I have the following:-
SUS_TIME2 shows what I get back from the SUBSTR and it looks fine at this point. SUS_TIME3 then shows what I get back after running it through the TO_DATE function, this where it converts it to 01-MAR-22
,SUBSTR((s.resolve_date-suspend_date),-16,9) sus_time2
,TO_DATE(SUBSTR((s.resolve_date-suspend_date),-16,9), 'hh24:mi:ss') sus_time3
Can anyone see what's going on here please? Thanks
Dates are stored in an internal representation and do not have any intrinsic format. What you are seeing is how your client is choosing to format the actual date value as a string for display, using your session's NLS_DATE_FORMAT setting (not always the case, but this is SQL Developer, so it is here.)
When you call to_date() with only the time components it defaults the date part to the first day of the current month, which is why you are seeing March 1st. That is a bit buried in the documentation:
If you specify a date value without a time component, then the default time is midnight. If you specify a date value without a date, then the default date is the first day of the current month.
But it is setting the time properly on that date, which you can see by either explicitly converting the date back to a string:
to_char(<your date>, 'YYYY-MM-DD HH24:MI:SS')
or by changing your session:
alter session set nls_date_format = 'YYYY-MM-DD HH24:MI:SS'
db<>fiddle
But you should not rely on NLS settings for anything except ad hoc queries; someone else running your code may have different settings. And only convert back to a string at the last moment when you have to display the value in a particular format - store it and pass it around as a native date.
Oracle doesn't have a time-only data type, so if you really only care about the time part then you can use a date (either defaulting to current month, or using an explicit fixed date) and ignore the date part; or potentially use an interval; or use the number of seconds the time represents (i.e. 0-86399). Which is suitable depends on what you'll use the value for.
It looks like you might be substringing the result of subtracting two timestamps; in which case (a) you already have an interval, and (b) you probably need to allow for that difference to span more than one day. You can also extract the individual time components directly from an interval value. So I'd question whether your approach is really appropriate.
You appear to be calculating s.resolve_date-suspend_date which gives you an INTERVAL DAY TO SECOND data type (implying that one or both of s.resolve_date or suspend_date is a TIMESTAMP data type) and then using SUBSTR to extract the time component of the data type and trying to convert that to a date and then display the time component.
Don't do that as using SUBSTR is fragile as it depends on the number of decimal places that the INTERVAL has which, in turn, will depend on the number of fractional seconds that the TIMESTAMP values have.
Just pick a date and add the interval to it and then format it as string to display it:
SELECT s.resolve_date,
suspend_date,
TO_CHAR(
DATE '1900-01-01' + (s.resolve_date-suspend_date),
'hh24:mi:ss'
) sus_time
FROM table_name s
Which, for the sample data:
CREATE TABLE table_name (resolve_date, suspend_date) AS
SELECT CAST(SYSTIMESTAMP AS TIMESTAMP(6)),
CAST(TRUNC(SYSTIMESTAMP) AS TIMESTAMP(6))
FROM DUAL;
Outputs:
RESOLVE_DATE
SUSPEND_DATE
SUS_TIME
2022-03-25 12:59:15.223445
2022-03-25 00:00:00.000000
12:59:15
From your comment:
all i'm trying to do is format the data so that when it's exported to Excel sorting works correctly.
That really is an XY-problem. You can solve it in Excel by either specifying the column format as a time when you import the data into Excel or right-click on the column header and "Format" the column picking the "time" data type with the correct format model.
You can also output the time as a fraction of a day with a numeric data type and then Excel can format it as the correct time using either:
SELECT s.resolve_date,
suspend_date,
MOD(CAST(s.resolve_date AS DATE)-CAST(suspend_date AS DATE), 1) AS sus_time
FROM table_name s;
or
SELECT s.resolve_date,
suspend_date,
TO_CHAR(DATE '1900-01-01' + (s.resolve_date-suspend_date), 'SSSSS')
/ 86400 AS sus_time
FROM table_name s
Which both output:
RESOLVE_DATE
SUSPEND_DATE
SUS_TIME
2022-03-25 13:16:40.204461
2022-03-25 00:00:00.000000
.5532407407407407407407407407407407407407
Which may not be human readable in that format but Excel will reformat it in a time column to 13:16:40.
db<>fiddle here

Oracle SQL Select Current Timestamp without Timezone and 24hr Format

I have a Oracle SQL statement where I have to get the current timestamp as one of the columns. But I dont require the Timezone which CURRENT_TIMESTAMP gives or the AM/PM given by LOCALTIMESTAMP.
I require the current timestamp in 24hr format without the timezone.
Is it possible to get that in Oracle SQL?
It seems you're mixing 2 concepts here: "datatype" and "date format mask".
data type: LOCALTIMESTAMP returns datatype TIMESTAMP and CURRENT_TIMESTAMP returns datatype TIMESTAMP WITH TIME ZONE. TIMESTAMP is similar to DATE but has a higher precision. As usual... checking the docs is worth it.
date format mask: determines how you display the date information. Americans can't read 24 hour format, the rest of the world is confused by AM/PM. Fortunately, you can decide how you want to display the date as explained in the oracle docs.
If you just want to return the current date in 24 hour format you could do something like:
SELECT
TO_CHAR(SYSDATE,'DD-MON-YYYY HH24:MI:SS') as mydate,
<other columns>
FROM
<table_name>
If you need the date to be more precise and you require fractional seconds then you can use SYSTIMESTAMP instead of DATE with a format mask 'DD-MON-YYYY HH24:MI:SS.FF9'

Convert datetime to UTC beginning of the day - Oracle db

For example:
I've got datetime in Oracle database like: 18/08/21 13:51:23,420460500 (y/m/d) and I want convert to type: 18/08/20 22:00:00,000000000.
Could you please let me know how can I do this?
I've tried SYS_EXTRACT_UTC("MyDate") but it does not work in that case.
From the format of your question, I'm assuming you have a TIMESTAMP value, since Oracle doesn't have a "datetime" data type. You can truncate the time component to midnight (the beginning of the day) with the TRUNC function, though it returns a DATE data type. I'm not sure where the 22:00 in your question is coming from.

Oracle SQL how to convert time zone string to date

I have following 2015-06-17T00:00:00.000+05:00 string.
I want to convert this string to Date using oracle sql.
I tried lot of format mask but none works for me :
SELECT TO_DATE('2015-06-17T00:00:00.000+05:00','yyyy-mm-dd HH24:MI:SS TZR') FROM DUAL;
Any idea which format mask should i apply for above conversion.
Also please note that i only need date information i.e (mm-dd-yyyy). So its also ok if the conversion results in date information only (i.e skipping time information)
This should work:
SELECT TO_DATE(SUBSTR('2015-06-17T00:00:00.000+05:00',1,10),'yyyy-mm-dd') from dual
If you need to keep track of the time zone you should probably look at something like this:
SELECT CAST(TO_TIMESTAMP_TZ('2015-06-17T00:00:00.000+05:00','yyyy-mm-dd"T"HH24:MI:SS.FFTZH:TZM') AT TIME ZONE 'UTC' AS DATE) FROM DUAL;

How to save date into 24 hours format in oracle

I am new to Oracle, and I need to save date and time in an Oracle database.
I am using time stamp as datatype for row. But now my problem is it saves date and time in 12 hours format like this 17/11/2011 10:10:10 PM.
But I need it in 24 hours format like 17/11/2011 22:10:10. I didn't understand the results that Google search result provided. Can any one please help me by posting some code.
Oracle always stores timestamps (and dates) in a packed binary format that is not human readable. Formatting is done only when a timestamp (or a date) is converted to a string.
You can control the formatting of your output by coding an explicit to_char. For example
SELECT to_char( your_timestamp_column, 'DD/MM/YYYY HH24:MI:SS' )
FROM your_table
Oracle stores timestamps in an internal format (with a default representation).
You can customize this representation on output like with the to_char() function.
For input (into the database) you can use to_date().