Mysql how to retrieve the data based on time? - mysql

I need to retrieve the data from table based on the time and date i.e I need to get the data from yesterday 5.00pm to current day till 5pm. I have tried the following code in which I retrieved the yesterday and today but with time it is not working help to solve this problem note:the column modified is in timestamp
SELECT *
FROM `mdl_forum_posts`
WHERE from_unixtime(modified, '%Y-%m-%d') = CURDATE()
OR from_unixtime(modified, '%Y-%m-%d') = date(CURDATE()-1)

SELECT * FROM `mdl_forum_posts`
WHERE modified BETWEEN UNIX_TIMESTAMP(
CONCAT(DATE_FORMAT(CURDATE()- INTERVAL 1 DAY, '%Y-%m-%d'), ' 17:00:00'))
AND UNIX_TIMESTAMP(
CONCAT(CURDATE(), ' 17:00:00'));
Note that CURDATE() is polymorphic; the DATE_FORMAT is required for the first predicate where the calculation forces an integer-like return type.
Wrapping attributes in functions within predicates disables the use of indexes - applying the inverse function to the literal allows the for use of indexes (and even in the absence of indexes will be faster as the function need only be evaulated once).

if the date 1st of the month CURDATE() - INTERVAL 1 DAY gives exact previous day date
SELECT * FROM `mdl_forum_posts`
WHERE modified BETWEEN UNIX_TIMESTAMP(
CONCAT(CURDATE() - INTERVAL 1 DAY, '%Y-%m-%d'), ' 17:00:00'))
AND UNIX_TIMESTAMP(
CONCAT(CURDATE(), ' 17:00:00'));

Related

Select records between a date in d-mY format and 1rst of next month, plus 1 day in Mysql

I need to select all data from a table 'followup' between followup_date and first of next month (including 1rst of next month). The format of my date in DB (obtained from an API) is d-m-Y.
The follow-up date for example is: 18-07-2020.
I have the following query:
SELECT * from followup
WHERE DATEDIFF(STR_TO_DATE(`followup_date`,'%d-%m-%Y'), DATE_FORMAT(CURDATE() + INTERVAL 1 MONTH,'%Y-%m-01'))- 1 < 0 ;
I am getting -15 days as difference and getting records correctly, including 1rst. Is the query correct and efficient and will it work correctly for all months.
Requesting suggestions from experts for improvements, if any.
You should convert your followup_date column to a DATE type. You can then make your query sargable by removing the function calls on followup_date and simply comparing it with the target date:
SELECT * from followup
WHERE `followup_date` <= DATE_FORMAT(CURDATE() + INTERVAL 1 MONTH,'%Y-%m-01')
I suspect adding one day to LAST_DAY(CURDATE()) might be more efficient:
SELECT * from followup
WHERE `followup_date` <= LAST_DAY(CURDATE()) + INTERVAL 1 DAY
Demo on SQLFiddle

mysql BETWEEN date range not working

I have a table called barcode_log, and these are all the datas from the table.
And now if I run this query
SELECT * FROM `barcode_log` WHERE barcode_log.assign_time BETWEEN DATE_SUB(CURRENT_DATE, INTERVAL 30 DAY) AND CURRENT_DATE;
I get this result
But it should return all the rows as all the data is within this month only. And assign_time field is stored as datetime. Any idea what i am doing wrong??
You are ignoring the time part (hh:mm:ss).
If the end day is set to the end timestamp of the current date then you can get the data of current day's too.
BETWEEN is inclusive
SELECT
*
FROM
`barcode_log`
WHERE
barcode_log.assign_time BETWEEN DATE_SUB(
CURRENT_DATE,
INTERVAL 30 DAY
)
AND TIMESTAMP(CONCAT(CURDATE(),' ','23:59:59'));
While the accepted answer works, there is a simpler solution. Just take the date part of the datetime column:
SELECT
*
FROM
`barcode_log`
WHERE
DATE(barcode_log.assign_time)
BETWEEN DATE_SUB(CURRENT_DATE, INTERVAL 30 DAY) AND CURRENT_DATE;
There is another way around: CAST() on barcode_log.assign_time field.
SELECT *
FROM `barcode_log`
WHERE CAST(barcode_log.assign_time AS DATE)
BETWEEN DATE_SUB(CURRENT_DATE, INTERVAL 30 DAY) AND CURRENT_DATE;
This excludes time from comparison and works fine for your purpose.

Select all MySQL records in the last day that are between a time range of 7am and midnight

I have this query
SELECT * FROM `timeclock_timecard`
WHERE `clock_in_datetime` > DATE_SUB(CURDATE(), INTERVAL 1 DAY)
which can get record in the last day but I need to limit to records created after 7AM
Any help please?
SELECT * FROM `timeclock_timecard`
WHERE `clock_in_datetime` > DATE_SUB(CURDATE(), INTERVAL 1 DAY)
and hour(`clock_in_datetime`) > 7;
Added one more filter condition to check for the hour.
Your query was almost correct, because CURDATE() only gives the date you can just subtract 17 hours to get the correct result. fiddle.
SELECT * FROM `timeclock_timecard`
WHERE `clock_in_datetime` >= DATE_SUB(CURDATE(), INTERVAL 17 HOUR)
To get the entries of the current day, we can add 7 hours (CURDATE() has time 0:00).
SELECT * FROM `timeclock_timecard`
WHERE `clock_in_datetime` >= DATE_ADD(CURDATE(), INTERVAL 7 HOUR)
To get only rows from yesterday, with a time value of 7AM or later, we can add 7 hours to the expression.
If we only up until midnight of today (just rows from yesterday), we can add another condition, the datetime is less than midnight today.
For example:
SELECT t.*
FROM `timeclock_timecard` t
WHERE t.`clock_in_datetime` >= DATE(NOW()) + INTERVAL -1 DAY + INTERVAL 7 HOUR
AND t.`clock_in_datetime` < DATE(NOW())
If you want to exclude the exact 7:00:00 AM value, change the >= to just >.
FOLLOWUP
Q: What I actually want is between about 5-6am TODAY and mindnight TODAY so anytime during today that I run the report for today I will get only timeclock data from users who clocked in/out today only and not include yesterdays data.
A: The predicates are going to be of the form
WHERE t.`clock_in_datetime` >= expr1
AND t.`clock_in_datetime` < expr2
You just need to find the expressions expr1 and expr2 that return the appropriate datetime values.
Just use a simple SELECT statement to test:
SELECT DATE(NOW()) + INTERVAL 5 HOUR AS `start`
, DATE(NOW()) + INTERVAL 1 DAY AS `end`
Q: I also modified my select to take in account my datetime is in UTC and my result needs to get todays records using local timezone.
SELECT * , CONVERT_TZ( clock_in_datetime , '+00:00', '-4:00' ) FROM `timeclock_timecard`
A: Personally, I would do the timezone conversion on the exprN values, not the column values. Having predicates on bare columns allows MySQL to make effective use of an index; wrapping the columns in expressions prevents MySQL from using an index.
If the MySQL system clock is UTC, and your datetime values stored in the table are in a different timezone, yes, use the MySQL CONVERT_TZ function.
Again, using a simple SELECT statement to develop and test the expressions:
SELECT CONVERT_TZ( DATE(NOW()) + INTERVAL 5 HOUR, '+0:00', to_tz) AS `start`
, CONVERT_TZ( DATE(NOW()) + INTERVAL 1 DAY , '+0:00', to_tz) AS `end`
Where to_tz is the timezone of the values in the table.
Once you get expressions start and end returning the values you need, then use those expressions in the predicates of the query of the timecard table.

MySQL Select rows <= now(), using separated time fields

I have a table 't' with date(yyyy-mm-dd), hour(1-12), minute(00-59), ampm(a/p), and timezone(pst/est) fields.
How can I select the rows that are <= now()? (ie. already happened)
Thank you for your suggestions!
edit: this does it without attention to the hour/minute/ap/tz fields:
SELECT * FROM t.date WHERE date <= now()
Here's one way to do it - combine all your seconds, minutes, etc into a date and compare to NOW(), making sure you do the comparison in the same time-zone. (Untested):
SELECT *
FROM t
LEFT JOIN y ON t.constant=y.constant
WHERE CONVERT_TZ(STR_TO_DATE(CONCAT(date,' ',hour,':',minute,' 'ampm),
'%Y-%m-%d %l:%i %p' ),
timezone,"SYSTEM") < NOW();
If your hour is 01 - 12 not 1-12 then use %h instead of %l in the STR_TO_DATE.
The STR_TO_DATE tries to stick your date and time columns together and convert them into a date.
The CONVERT_TZ(...,timezone,"SYSTEM") converts this date from whatever timezone is specified in the timezone column to system time.
This is then compared to NOW(), which is always in system time.
As an aside, perhaps you should make a single column date using MySQL's date datatype, as it's a lot easier to do arithmetic on that!
For reference, here is a summary of very useful mysql date functions where you can read up on those featuring in this answer.
Good luck!
SELECT * FROM t
WHERE `date`<=DATE_SUB(curdate(), INTERVAL 1 DAY)
OR (
`date`<=DATE_ADD(curdate(), INTERVAL 1 DAY)
AND
CONVERT_TZ(CAST(CONCAT(`date`,' ',IF(`hour`=12 AND ampm='a',0,if(ampm='a',`hour`,`hour`+12)),':',`minute`,':00') AS DATETIME),'GMT',`timezone`)<=NOW()
)
Rationale for date<=DATE_[ADD|SUB](curdate(), INTERVAL 1 DAY):
The fancy conversion is quite an expensive operation, so we don't want it to run on the complete table. This is why we pre-select against an UNCHANGED date field (possibly using an index). In no timezone can an event being more than a day in current timezone's past be in the future, and in no timezone can an event more than a day in the curent timezone's future be in the past.

How to get first day of every corresponding month in mysql?

I want to get first day of every corresponding month of current year. For example, if user selects '2010-06-15', query demands to run from '2010-06-01' instead of '2010-06-15'.
Please help me how to calculate first day from selected date. Currently, I am trying to get desirable using following mysql select query:
Select
DAYOFMONTH(hrm_attendanceregister.Date) >=
DAYOFMONTH(
DATE_SUB('2010-07-17', INTERVAL - DAYOFMONTH('2010-07-17') + 1 DAY
)
FROM
hrm_attendanceregister;
Thanks
Is this what you are looking for:
select CAST(DATE_FORMAT(NOW() ,'%Y-%m-01') as DATE);
You can use the LAST_DAY function provided by MySQL to retrieve the last day of any month, that's easy:
SELECT LAST_DAY('2010-06-15');
Will return:
2010-06-30
Unfortunately, MySQL does not provide any FIRST_DAY function to retrieve the first day of a month (not sure why). But given the last day, you can add a day and subtract a month to get the first day. Thus you can define a custom function:
DELIMITER ;;
CREATE FUNCTION FIRST_DAY(day DATE)
RETURNS DATE DETERMINISTIC
BEGIN
RETURN ADDDATE(LAST_DAY(SUBDATE(day, INTERVAL 1 MONTH)), 1);
END;;
DELIMITER ;
That way:
SELECT FIRST_DAY('2010-06-15');
Will return:
2010-06-01
There is actually a straightforward solution since the first day of the month is simply today - (day_of_month_in_today - 1):
select now() - interval (day(now())-1) day
Contrast that with the other methods which are extremely roundabout and indirect.
Also, since we are not interested in the time component, curdate() is a better (and faster) function than now(). We can also take advantage of subdate()'s 2-arity overload since that is more performant than using interval. So a better solution is:
select subdate(curdate(), (day(curdate())-1))
This is old but this might be helpful for new human web crawlers XD
For the first day of the current month you can use:
SELECT LAST_DAY(NOW() - INTERVAL 1 MONTH) + INTERVAL 1 DAY;
You can use EXTRACT to get the date parts you want:
EXTRACT( YEAR_MONTH FROM DATE('2011-09-28') )
-- 201109
This works well for grouping.
You can use DATE_FORMAT() function in order to get the first day of any date field.
SELECT DATE_FORMAT(CURDATE(),'%Y-%m-01') as FIRST_DAY_CURRENT_MONTH
FROM dual;
Change Curdate() with any other Date field like:
SELECT DATE_FORMAT(purchase_date,'%Y-%m-01') AS FIRST_DAY_SALES_MONTH
FROM Company.Sales;
Then, using your own question:
SELECT *
FROM
hrm_attendanceregister
WHERE
hrm_attendanceregister.Date) >=
DATE_FORMAT(CURDATE(),'%Y-%m-01')
You can change CURDATE() with any other given date.
There are many ways to calculate the first day of a month, and the following are the performance in my computer (you may try this on your own computer)
And the winner is LAST_DAY(#D - interval 1 month) + interval 1 day
set #D=curdate();
select BENCHMARK(100000000, subdate(#D, (day(#D)-1))); -- 33 seconds
SELECT BENCHMARK(100000000, #D - INTERVAL (day(#D) - 1) DAY); -- 33 seconds
SELECT BENCHMARK(100000000, cast(DATE_FORMAT(#D, '%Y-%m-01') as date)); -- 29 seconds
SELECT BENCHMARK(100000000, LAST_DAY(#D - interval 1 month) + interval 1 day); -- 26 seconds
I'm surprised no one has proposed something akin to this (I do not know how performant it is):
CONCAT_WS('-', YEAR(CURDATE()), MONTH(CURDATE()), '1')
Additional date operations could be performed to remove formatting, if necessary
use date_format method and check just month & year
select * from table_name where date_format(date_column, "%Y-%m")="2010-06"
SELECT LAST_DAY(date) as last_date, DATE_FORMAT(date,'%Y-%m-01') AS fisrt_date FROM table_name
date=your column name
The solutions that use last_day() and then add/subtract a month and a day are not interchangeable.
Example:
date_sub(date_add(last_day(curdate()), interval 1 day), interval 3 month)
always works for any supplied number of months you want to go back
date_add(date_sub(last_day(now()), interval 3 month), interval 1 day)
will fail in some cases, for instance if your current month has 30 days and the month you're subtracting back to (and then adding a day) has 31.
date_add(subdate(curdate(), interval day(?) day), interval 1 day)
change the ? for the corresponding date
This works fine for me.
date(SUBDATE("Added Time", INTERVAL (day("Added Time") -1) day))
** replace "Added Time" with column name
Use Cases:
If you want to reset all date fields except Month and Year.
If you want to retain the column format as "date". (not as "text" or "number")
Slow (17s):
SELECT BENCHMARK(100000000, current_date - INTERVAL (day(current_date) - 1) DAY);
SELECT BENCHMARK(100000000, cast(DATE_FORMAT(current_date, '%Y-%m-01') as date));
If you don't need a date type this is faster:
Fast (6s):
SELECT BENCHMARK(100000000, DATE_FORMAT(CURDATE(), '%Y-%m-01'));
SELECT BENCHMARK(100000000, DATE_FORMAT(current_date, '%Y-%m-01'));
select big.* from
(select #date := '2010-06-15')var
straight_join
(select * from your_table where date_column >= concat(year(#date),'-',month(#date),'-01'))big;
This will not create a full table scan.