I have the following in a SQL Server query which I have to convert to Oracle sp
DATEADD(dd, 0, DATEDIFF(dd, 0, DATEADD(ss, -L_LAST_TIME, TR.TR_DATETIME))) AS TRDATE,
Essentially you subtract L_LAST_TIME seconds from TR_DATETIME and then truncate the time part and keep only the date part.
You can divide intervals:
select trunc(TR.TR_DATETIME - interval L_LAST_TIME SECOND) AS TRDATE
or
select trunc(TR.TR_DATETIME - NUMTODSINTERVAL(L_LAST_TIME, 'SECOND')) AS TRDATE
We can do arithmetic with dates in Oracle.
select trunc(tr.tr_time - (l_last_time/86400)) as trdate
from tr
/
Dividing l_last_time by 86400 turns a number of seconds into a fraction of day. Subtracing it from the tr_time column gives you a new, earlier date. Truncating a date removes the time component.
Related
I need to calculate hours between datetime fields and I can achieve it by simply doing
select date1,date2,(date1-date2) from table; --This gives answer in DD:HH:MM:SS format
select date1,date2,(trunc(date1)-trunc(date2))*24 --This doesn't take into account the time, it only gives hours between two dates.
Is there a way I can find the difference between date times that gives the output in Hours as a number?
The 'format' comment on your first query suggests your columns are timestamps, despite the dummy column names, as the result of subtracting two timestamps is an interval. Your second query is implicitly converting both timestamps to dates before subtracting them to get an answer as a number of days - which would be fractional if you weren't truncating them and thus losing the time portion.
You can extract the number of hours from the interval difference, and also 24 * the number of days if you expect it to exceed a day:
extract(day from (date1 - date2)) * 24 + extract(hour from (date1 - date2))
If you want to include fractional hours then you can extract and manipulate the minutes and seconds too.
You can also explicitly convert to dates, and truncate or floor after manipulation:
floor((cast(date1 as date) - cast(date2 as date)) * 24)
db<>fiddle demo
Use the DATEDIFF function in sql.
Example:
SELECT DATEDIFF(HOUR, '2021-09-05 12:00:00', GETDATE());
You can find it using the differnece of dates and multiplying with 24
select date1
,date2
,(date1-date2)*24 as diff_in_hrs
from table
This query is happening in Redshift whose SQL idiosyncrasies drive me crazy.
I have a UNIX epoch timestamp in my table and I need to filter for the most recent seven days. Redshift lacks the from_unixtime() function so I've hacked this together. tb_h is the UNIX date column. 604800000 is the number of milliseconds in a seven day period.
"tb_h" >= DATE_PART(epoch, DATEADD(milliseconds, -604800000, DATEADD(day, -1, trunc(getdate()))))
This workaround doesn't filter on the last seven, it allows all dates through. What's my logical error here?
What happens if you use a more reasonable type for the subtraction?
"tb_h" >= DATE_PART(epoch, DATEADD(day, -7, DATEADD(day, -1, CURRENT_DATE)))
Second, in Postgres, epoch returns the number of seconds -- and I'm not sure if Redshift is the same. If your value is in milliseconds or microseconds, you need to multiply:
"tb_h" >= 1000 * DATE_PART(epoch, DATEADD(day, -8, CURRENT_DATE))
Not being that great at sql, i've reached my limit.
I have a date in the yyyy/mm/dd format and i need to get all records "from a week ago"
I think i need some conversion stuff to be done cause this
d.date_begin >= DATEADD(day,-7, GETDATE())
is not working :), i'm TERRIBLE at convert and data type..
This will work if you want records from 7 days ago up to and including today's records
CAST(d.date_begin AS DATE) >= CAST(DATEADD(day,-7, GETDATE()) AS DATE)
where DATEDIFF(month,Your_date_column,getdate()) < 3
SQL server 2012 onwards, if date_begin is of datatype date
where d.date_begin >= cast(DATEADD(day,-7, GETDATE()) as date)
This will get anything in the last 7 days, regardless of time
You should store date/time values using native formats. Ok, sometimes we cannot. But you can easily convert your values to the correct format:
where cast(replace(d.date_begin, '/', '') as date) >= DATEADD(day, -7, GETDATE())
I should note that SQL Server is pretty good about conversions, so your initial code should not generate any errors -- unless you have unusual internationalization settings.
Or, actually, a better way to do this is to convert the current value to a string:
where d.date_begin >= format(dateadd(day, -7, getdate()), 'yyyy/MM/dd')
This is better because it is "sargable", meaning that SQL Server can use an index on the column if available.
SELECT * FROM tbl_name
WHERE date >= curdate() - INTERVAL DAYOFWEEK(curdate())+6 DAY
AND date < curdate() - INTERVAL DAYOFWEEK(curdate())-1 DAY
Don't manipulate d.date_begin. Making calculation on a column while comparing can give bad performance. You should manipulate getdate() to get the same format as d.date_begin. In this case it works because the format is yyyy/MM/dd - the comparison will give the same result as if both columns were date columns.
WHERE
d.date_begin >= convert(char(10),DATEADD(day,-7, GETDATE()), 111)
I have SQL script that selects everything from current day.
SELECT [ClientID] from [logs] where Date > CONVERT (date, SYSDATETIME())
Date is type of DateTime.
How to get everything within last 3 days? I suppose I need subtract 3 days from function SYSDATETIME() result, but how?
SELECT [ClientID] from [logs] where Date > DATEADD(day, -3, CONVERT (date, SYSDATETIME()))
Use GETDATE() : Yes, it gets date from system!
Returns the current database system timestamp as a datetime value
without the database time zone offset. This value is derived from the
operating system of the computer on which the instance of SQL Server
is running.
Query:
SELECT [ClientID] from [logs] where ( Date > GETDATE() - 3)
More Reference:
GETDATE Detailed Documentation
For mysql use this:
SELECT DATE_ADD(CURRENT_DATE, INTERVAL - 3 DAY);
Use BETWEEN
SELECT ClientID
FROM logs
WHERE Date BETWEEN SYSDATETIME() AND SYSDATETIME() - 3
Using BETWEEN is nice. I also prefer the DATEADD function. But be aware of the fact that the SYSDATETIME function (or I would us GETDATE()) also includes the time which would mean that events before the current time but within the three day period may not be included. You may have to convert both sides to a date instead of datetime.
SELECT [ClientID] from [logs] where Date > DATEADD(day, -3, SYSDATETIME())
In my case:
select * from Table where row > now() - INTERVAL 3 day;
So you can fetch all of 3 days ago!
I would like the below select statement to be show as time rather than datetime. I'm aware that a cast as solution is likely however given I am trying to Cast as a "grouped by time", I am not finding a solution.
SELECT
DATEADD(hour, DATEDIFF(hour, 0,dbo.tbReceiptLine.Time), 0) AS Hourly,
DATEADD(minute, DATEDIFF(minute, 0, dbo.tbReceiptLine.Time) / 30 * 30, 0) AS [30 Mins]
I would like to show this as time only.
In SQL Server 2008 onwards you can cast to time datatype:
SELECT CAST(dbo.tbReceiptLine.Time as time)
See The ultimate guide to the datetime datatypes