I am trying to find the timestamp of a certain day of the week with postgrSQL. For example, one might use now() to get the current time, but I want to get the same type of data return for, say, the most recent Monday or Sunday.
I am looking for this because I have a query which retrieves data between now and a few months ago and I don't want to include the current week. As an example what it does now:
creation_date > now() - INTERVAL '2 month'
I thought this might achieve my goals:
BETWEEN now() - INTERVAL '4 month' AND now() - INTERVAL '1 week'
But it just subtracts 7 days from the query which is not what I want. Basically, I want:
BETWEEN now() - INTERVAL '4 month' AND ????
Where the question marks are timestamp for the most recent Sunday, at least I believe that would work.
date_trunc('week', current_date) - interval '1' day
date_trunc('week', current_date) will return the date at the start of the week.
The start of the week is always Monday in Postgres. That's why you need to subract another day from the result to get the Sunday.
You can extract the current day of the week (0-6, Sunday is 0) using EXTRACT(DOW FROM date). You could then use this to create an interval to add or subtract to reach a particular weekday. For example, the most recent Sunday would be now() - (EXTRACT(DOW FROM now()) || ' days')::interval.
Related
I want to Increment/Decrement the Year , Day , Month by pulling in the Current Date in Snowflake in a single query ?
For e.g.
Suppose Current System Date - 04082021 I want to make it 05092022. I have tried the dateadd function but I suppose it allows only one part i.e. either year or month or day to be incremented at once.
Is it Possible ? If Not, What are the other alternatives ?
If you want to useDATEADD function, here is the code:
SELECT DATEADD(YEAR,+1,DATEADD(MONTH,+1,DATEADD(DAY,+1,CURRENT_DATE())));
returns 2022-09-05 from 2021-08-04
If you want to keep your format, Please use following code
SELECT TO_CHAR(DATEADD(YEAR,+1,DATEADD(MONTH,+1,DATEADD(DAY,+1,CURRENT_DATE()))),'DDMMYYYY');
I would do the arithmetic in thee parts:
select current_date + interval '1 year' + interval '1 month' + interval '1 day'
You can also use:
select current_date + interval '1 year, 1 month, 1 day'
I want to extract data for a week from previous day.
For example:
Today's date : 21-06-2021
I want a week's data from : 13-06-2021 to 20-06-2021
In Postgressql
you can try
select * from ur_tbl
where
date_clmn >= (CURRENT_DATE - INTERVAL '7 day') and
date_clmm < CURRENT_DATE
My goal is to have the query grab data from 2 days ago. I don't want to have to keep inputting the date like this:
WHERE usage_start_date
BETWEEN TIMESTAMP '2020-09-09 00:00:00.000' and TIMESTAMP '2020-09-09
23:59:59.999'
but instead something like:
usage_start_date = current_date - interval '2' day
the above works for my Athena Presto SQL query, but for some reason will not give all the data that ran in those 24 hours, instead giving about half the day. Is there a way to do a statement like this one to ensure it gives ALL data in that day?
WHERE current_date - interval '2' day AND
BETWEEN TIMESTAMP '00:00:00.000' and TIMESTAMP '23:59:59.999'
without inputting the year, month, day? It seems like TIMESTAMP needs the y/m/d but what about doing a LIKE so it picks up the hour, minute, second but no need to put the y/m/d?
To get a timestamp for the start of the day that was two days ago you can do
DATE_TRUNC('day', NOW() - INTERVAL '2' DAY)
e.g.
WHERE usage_start_date >= DATE_TRUNC('day', NOW() - INTERVAL '2' DAY)
AND usage_start_date < DATE_TRUNC('day', NOW() - INTERVAL '1' DAY)
You can use below query to achieve the task by fetching the hour and date from the usage_start_date
select * from table where hour(usage_start_date) between 0 and 23 and current_date - interval '2' day = date(usage_start_date)
I would suggest:
WHERE usage_start_date >= CURRENT_DATE - INTERVAL '2' DAY AND
usage_start_date < CURRENT_DATE - INTERVAL '1' DAY
I'm trying to get the data between last weeks monday and last week sunday. I'm having trouble with getting the relative part. I'm trying like this:
where date <= LASTWEEKSUNDAY OR date >= LASTWEEKMON
The closest I got to what I seek was using now(), but it returned also some days from the current week. Thanks in advance
You are describing:
where date >= date_sub(date_trunc(current_date, week(Monday), interval 1 week) and
date < date_trunc(current_date, week(Monday))
Although the function calls change, the same logic works on datetimes and timestamps.
Of course week(Monday) is the default for isoweek, so you can use:
where date >= date_sub(date_trunc(current_date, isoweek, interval 1 week) and
date < date_trunc(current_date, isoweek)
I think it's what you want
where date between DATE_SUB(DATE_TRUNC(CURRENT_DATE(), WEEK(SUNDAY)), interval 6 day) and DATE_TRUNC(CURRENT_DATE(), WEEK(SUNDAY))
You shouldn't use OR in the where statement, it'll cover all the days if you use OR. Instead, you can prefer using AND or between.
I have a table(pkg_date) in redshift. I want to fetch some data for every date for the last 3 months.
Here is my query
select * from pkg_data where scan_date < current_date;
How can I use current_date as a variable in the query itself and run this query for every date from April 1.
I have set a cron job which will run in every hour. In every hour it should run with different current_date
SELECT *
FROM pkg_data
WHERE scan_date > CURRENT_DATE - INTERVAL '3 months'
Be careful — Redshift works in UTC, so the CURRENT_DATE might suffer from timezone effects and be +/- what you expect sometimes.
SELECT
CURRENT_DATE,
(CURRENT_DATE - INTERVAL '3 months')::date
Returns:
2018-06-21 2018-03-21
Also be careful with strange lengths of months!
SELECT DATE '2018-05-31' - INTERVAL '3 months'
returns:
2018-02-28 00:00:00
Notice that it gave the last day of the month (31st vs 28th).
By the way, you can use DATE '2018-05-31' or '2018-05-31'::DATE, and also INTERVAL '3 months' or '3 months'::INTERVAL to convert types.
Use dateadd() for getting date 3 moth old day and GETDATE() for get current date.
ie code will look like.
select * from pkg_data where scan_date < dateadd(month,-3,GETDATE());
for cron refer How to execute scheduled SQL script on Amazon Redshift?