I want to format date in a column where date formats are mixed like d/mm/yy, d/m/yy, dd/mm/yyyy where i want ot format all values should be in one format like mm/dd/yyyy in sqlite database
SQLite does not support built-in date and/or time storage class. Instead, it leverages some built-in date and time functions to use other storage classes such as TEXT, REAL, or INTEGER for storing the date and time values.
use the TEXT storage class for storing SQLite date and time https://www.sqlitetutorial.net/sqlite-date/
This will convert month, day, year divided by slashes into year, month, day divided by dashes. For example 2/19/1921 into 1921-2-19. Just uses basic SQL with a subquery.
SELECT
surveydate
,Substr(dayyear, Instr(dayyear, '/') + 1, 999) || '-' || -- Year
month || '-' || -- Month
Substr(dayyear, 0, Instr(dayyear, '/')) -- Day
AS surveydate2
FROM (
SELECT
surveydate,
Substr(surveydate, 0, Instr(surveydate, '/')) AS month,
Substr(surveydate, Instr(surveydate, '/') + 1, 999) AS dayyear
FROM "input_locations"
)
Related
This question already has an answer here:
Split quarters to individual months
(1 answer)
Closed 3 months ago.
I need to convert a yyyy/dd varchar type data( ex: 2021/03) to a monthly sort of date. (Ex: 2021/01, 2021/02, 2021/03). So, i need to convert the quarterly format to a monthly format in snowflake. Can we do this?
I tried many things but didn't get the expected results
select TO_DATE(date_column, 'YYYY/MM')
It may help to have a calendar table in your environment to deal with more complicated date conversions like this. An example of what this table may look like is in this CTE below. The SELECT statement following converts a string date of format YYYY/QQ of '2021/03' to YYYY/MM
WITH calendar AS
(
SELECT
dateadd('DAY', seq4(), '2000-01-01'::DATE) as calendar_date,
MONTH(calendar_date) as month_of_year,
QUARTER(calendar_date) as quarter_of_year,
YEAR(calendar_date) as year_of_calendar,
DAY(calendar_date) as day_of_month,
WEEK(calendar_date) as week_of_year
FROM table(generator(rowcount => 365*50))
)
SELECT DISTINCT '2021/03' as YYYYQQ_date,
year_of_calendar || '/' || LPAD(month_of_year, 2, '0') as YYYYMM
FROM calendar
WHERE year_of_calendar = strtok(YYYYQQ_date, '/', 1)
AND quarter_of_year = strtok(YYYYQQ_date, '/', 2);
2021/07
2021/08
2021/09
That's merely an example for turning yyyy/qq into multiple yyyy/mm outputs for that quarter, but this same logic can be applied to any date-part conversion and the calendar table can be customized to hold even organization-specific date things like oddball fiscal periods, company holiday flags, or a business day flag (as an example).
I have an INT64 column called "Date" which contains many different numbers like: "20210209" or "20200305". I want to turn those numbers into a date with this format: MM-YYYY (so in these cases, 02-2021 and 03-2020). Ultimately I want to sum all the data in each month together. The problem is that BigQuery can't convert INT64 to date, only to strings. I'm not sure if I should convert to a string and then to a date or if there is a better way.
Although converting to a string then a date both works and is very concise, over large enough numbers of rows (which may be the case in Big Query) you may be better off using integer maths and using DATE(year, month, day)...
https://cloud.google.com/bigquery/docs/reference/standard-sql/date_functions#date
SELECT
DATE(
DIV( 20210209 , 10000), -- Which gives 2021
DIV(MOD(20210209, 10000), 100), -- Which gives 02
MOD(20210209, 100) -- Which gives 09
)
You can convert the value to a string and use parse_date():
select parse_date('%Y%m%d', cast(20210209 as string))
Another option
select date,
regexp_replace('' || date, r'(\d{4})(\d{2})(\d{2})', r'\2-\1') as MM_YYYY
from your_table
if applied to sample data in your question - output is
Yet another option
select date,
format_date('%m-%Y', parse_date('%Y%m%d', '' || date)) as MM_YYYY
from your_table
with same output
My DB contains a period(month) and a year - I am trying to convert it to a date. I don't care for the actual day of the month so I have just made it "1" (the 1st of the month).
In my code I had to convert the "13th" period to the 12th because of the 12 months of the year, so my decode did that part... Ultimately, I want it to return as a date. I have a concatenation to make it 'look' like a date, but not actually a date.
What i do with the data is query it and return it in Excel for further manipulation. When imported to Excel, it does not import as a date nor does it let me convert to a date format.
SELECT DIA_PROJECT_DETAIL.FY_DC || '/' ||
decode(DIA_PROJECT_DETAIL.PER_DC,1,1,2, 2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,12)||
'/01' as "Date"
FROM AMS.DIA_PROJECT_DETAIL DIA_PROJECT_DETAIL
There has to be an easier or more effective way to do this!
There is no much simpler way. DECODE is fine for converting month 13 to month 12, but you use it a bit too complicated. Then you shouldn't rely on session settings, but explicitly tell the DBMS the date format your assembled string represents. Use TO_DATE with the appropriate format.
select
to_date(fy_dc || to_char(decode(per_dc, 13, 12, per_dc), '00') || '01', 'yyyymmdd')
as "Date"
from ams.dia_project_detail dia_project_detail;
Just use least():
SELECT (DIA_PROJECT_DETAIL.FY_DC || '/' ||
LEAST(DIA_PROJECT_DETAIL.PER_DC, 12) ||
'/01'
) as "Date"
FROM AMS.DIA_PROJECT_DETAIL DIA_PROJECT_DETAIL;
I am using Hive, so the SQL syntax might be slightly different. How do I get the data from the previous month? For example, if today is 2015-04-30, I need the data from March in this format 201503? Thanks!
select
employee_id, hours,
previous_month_date--YYYYMM,
from
employees
where
previous_month_date = cast(FROM_UNIXTIME(UNIX_TIMESTAMP(),'yyyy-MM-dd') as int)
From experience, it's safer to use DATE_ADD(Today, -1-Day(Today)) to compute last-day-of-previous-month without having to worry about edge cases. From there you can do what you want e.g.
select
from_unixtime(unix_timestamp(), 'yyyy-MM-dd') as TODAY,
date_add(from_unixtime(unix_timestamp(), 'yyyy-MM-dd'), -1-cast(from_unixtime(unix_timestamp(), 'd') as int)) as LAST_DAY_PREV_MONTH,
substr(date_add(from_unixtime(unix_timestamp(), 'yyyy-MM-dd'), -1-cast(from_unixtime(unix_timestamp(), 'd') as int)), 1,7) as PREV_MONTH,
cast(substr(regexp_replace(date_add(from_unixtime(unix_timestamp(), 'yyyy-MM-dd'), -1-cast(from_unixtime(unix_timestamp(), 'd') as int)), '-',''), 1,6) as int) as PREV_MONTH_NUM
from WHATEVER limit 1
-- today last_day_prev_month prev_month prev_month_num
-- 2015-08-13 2015-07-30 2015-07 201507
See Hive documentation about date functions, string functions etc.
below works across year boundaries w/o complex calcs:
date_format(add_months(current_date, -1), 'yyyyMM') --previous month's yyyyMM
in general,
date_format(add_months(current_date, -n), 'yyyyMM') --previous n-th month's yyyyMM
use proper sign for needed direction (back/ahead)
You could do (year('2015-04-30')*100+month('2015-04-30'))-1 for the above mentioned date, it will return 201503 or something like (year(from_unixtime(unix_timestamp()))*100+month(from_unixtime(unix_timestamp())))-1 for today's previous month. Assuming your date column is in 'yyyy-mm-dd' format you can use the first example and substitute the date string with your table column name; for any other format the second example will do, add the column name in the unix_timestamp() operator.
Angelo's reply is a good start but it returns 201500 if the original date was 2015-01-XX. Building on his answer, I suggest using the following:
IF(month(${DATE}) = 1,
(year(${DATE})-1)*100 + 12,
year(${DATE})*100 + month(${DATE})-1
) as month_key
provided you get rid of those hyphens in your input string , previous date's month id in YYYYMM format you can get by:-
select if( ((${hiveconf:MonthId}-1)%100)=0 ,${hiveconf:MonthId}-89,${hiveconf:MonthId}-1 ) as PreviousMonthId;
I am running sqlite to select data between two ranges for a sales report. To select the data from between two dates I use the following statement:
SELECT * FROM test WHERE date BETWEEN "11/1/2011" AND "11/8/2011";
This statement grabs all the dates even those outside the criteria. The date format you see entered is in the same format that I get back. I'm not sure what's wrong.
SQLite requires dates to be in YYYY-MM-DD format. Since the data in your database and the string in your query isn't in that format, it is probably treating your "dates" as strings.
Change your data to that formats to use sqlite datetime formats.
YYYY-MM-DD
YYYY-MM-DD HH:MM
YYYY-MM-DD HH:MM:SS
YYYY-MM-DD HH:MM:SS.SSS
YYYY-MM-DDTHH:MM
YYYY-MM-DDTHH:MM:SS
YYYY-MM-DDTHH:MM:SS.SSS
HH:MM
HH:MM:SS
HH:MM:SS.SSS
now
DDDDDDDDDD
SELECT * FROM test WHERE date BETWEEN '2011-01-11' AND '2011-08-11'
One more way to select between dates in SQLite is to use the powerful strftime function:
SELECT * FROM test WHERE strftime('%Y-%m-%d', date) BETWEEN "11-01-2011" AND "11-08-2011"
These are equivalent according to https://sqlite.org/lang_datefunc.html:
date(...)
strftime('%Y-%m-%d', ...)
but if you want more choice, you have it.
SELECT *
FROM TableName
WHERE julianday(substr(date,7)||'-'||substr(date,4,2)||'-'||substr(date,1,2)) BETWEEN julianday('2011-01-11') AND julianday('2011-08-11')
Note that I use the format: dd/mm/yyyy.
If you use d/m/yyyy, Change in substr().
Or you can cast your string to Date format with date function. Even the date is stored as TEXT in the DB.
Like this (the most workable variant):
SELECT * FROM test WHERE date(date)
BETWEEN date('2011-01-11') AND date('2011-08-11')
SQLite does not have a concept of dates. It only knows them as text. When you do this in SQLite you're actually doing string comparisons. You can read more from the official documentation.
When two TEXT values are compared an appropriate collating sequence is used to determine the result.
Any numeric (i.e., not using words like 'May') format for dates that is padded and in order from biggest field to smallest field will work. "2021-05-07" (May 7th) comes before "2021-05-09" (May 9th). So if you use "yyyy-mm-dd" format then you'll be set. "yyyy/mm/dd" and "yyyymmdd" work just fine too. (For a better phrasing on "sortable" date formats check out RFC 3339 section 5.1.)
A reason to use "yyyy-mm-dd" format is because that's the format that SQLite's builtin date uses.
Special thanks to Jeff and vapcguy your interactivity is really encouraging.
Here is a more complex statement that is useful when the length between '/' is unknown::
SELECT * FROM tableName
WHERE julianday(
substr(substr(date, instr(date, '/')+1), instr(substr(date, instr(date, '/')+1), '/')+1)
||'-'||
case when length(
substr(date, instr(date, '/')+1, instr(substr(date, instr(date, '/')+1),'/')-1)
)=2
then
substr(date, instr(date, '/')+1, instr(substr(date, instr(date, '/')+1), '/')-1)
else
'0'||substr(date, instr(date, '/')+1, instr(substr(date, instr(date, '/')+1), '/')-1)
end
||'-'||
case when length(substr(date,1, instr(date, '/')-1 )) =2
then substr(date,1, instr(date, '/')-1 )
else
'0'||substr(date,1, instr(date, '/')-1 )
end
) BETWEEN julianday('2015-03-14') AND julianday('2015-03-16')
Put the variable in the Where Condition and parse both dates using 'BETWEEN':
SELECT * FROM emp_master
-> if you have date formate like dd/mm/yyyy simple then,
WHERE joined_date BETWEEN '01/03/2021' AND '01/09/2021';
-> and if you have date formate like yyyy/mm/dd then,
WHERE joined_date BETWEEN '2021/03/01' AND '2021/09/01';
☻♥ Done Keep Code.
Let's say you are preparing data for some report. Then the whole ordeal will look similar to this.
--add column with date in ISO 8601
ALTER TABLE sometable ADD COLUMN DateInISO8601;
--update the date from US date to ISO8601 date
UPDATE sometable
SET DateInISO8601 = substr([DateInUSformat],length([DateInUSformat])+1, -4)
|| '-' ||
substr('00' || [DateInUSformat],instr('00' || [DateInUSformat],'/'),-2)
|| '-' ||
substr('00' || rtrim(substr([DateInUSformat],instr([DateInUSformat],'/')+1,2),'/'),-2,2);
SELECT DateInISO8601
FROM sometable
WHERE DateInISO8601 BETWEEN '2022-02-02' AND '2022-02-22';
You can of course do all that on the fly, but if you have the choice -- don't. Use the ISO date by default and convert it on the way in and out to SQLite DB.