Our table has start_time and end_time as unix epoch timestamps. I'd like to find all the rows where the end_time is exactly 14 hours (50400) greater than the start time.
SELECT * FROM `mrbs_entry` WHERE (`end_time`-`start_time`)==50400
This seems slightly off, and in fact doesn't work. I'm not sure what the proper terminology to search though.
You shouldn't use == for comparing the values, but =.
Or you can use FROM_UNIXTIME to format is as date and then DATESUB with INTERVAL 14 HOUR. So it's:
SELECT * FROM `mrbs_entry`
WHERE DATE_SUB(FROM_UNIXTIME(`end_time`), INTERVAL 14 HOUR) = FROM_UNIXTIME(`start_time`);
Related
I've got a column time type in mysql, i want to add 24 hours to this hour, i try with code below:
SELECT SUBSTRING(CAST(DATE_ADD(STR_TO_DATE('23:00', '%k:%i'), INTERVAL (TIME_TO_SEC('24:00') / 60) MINUTE) AS CHAR(8)), 1,5)
I need to return 23:00 again (because i add 24 hours but that 23:00 is of the next day) but this code return me 47:00.
Some help?
I think you're looking for ADDTIME
SELECT ADDTIME(‘23:00’,’24:00’)
https://dev.mysql.com/doc/refman/5.7/en/date-and-time-functions.html#function_addtime
You need to first convert the column value to a datetime, add the hours, and then convert the result back to time:
select cast(date_add(cast(time_column as datetime), interval 24 hour ) as time)
from yourtable;
Example:
select cast(date_add(cast(cast('23:00' as time) as datetime), interval 24 hour ) as time)
The TIME type allows you to store up to (but not including) 839 hours (positive and negative). That's great if you need to store duration, but not so much if you want to store time of day. If you want the latter you should consider the DATETIME type instead.
Why this query is not working
SELECT * FROM history WHERE DATE(date) < CURDATE() + 30
I am trying to get the data from 30 days but my query is not working.Why
What does +30 mean? Days? Years? Months? Hours? You need to use (the proper syntax) a format MySQL understands:
SELECT * FROM history WHERE DATE(date) < CURDATE() + INTERVAL 30 DAY
To get the data from today on to 30 days after current day, you've got to set an upper and an lower limit, so use:
SELECT * FROM history WHERE
date >= CURDATE()
AND
date < CURDATE() + INTERVAL 31 DAY
Please note that by not using a function on your date column you won't prohibit MySQL to use an index on this column.
The lower limit should be obvious, the upper limit means that you've got the complete day that's 30 days later than today. If you use + INTERVAL 30 DAY instead this last day is excluded from the result.
Because you're not using the right construct, try:
SELECT * FROM history WHERE DATE_ADD(date, INTERVAL 30 DAY);
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.
I am using this function to filter query results that are older than 60 days:
s.timeSubmitted >= ( CURDATE() - INTERVAL 60 DAY )
The problem is, the "60 days" part doesn't seem to be an exact figure. I want it to filter right where s.timeSubmitted is longer than 60 days, down to the exact second of s.timeSubmitted.
How do I write "60 Days" as an exact figure (down to the second)?
The problem is that CURDATE() returns a DATE type, not a DATETIME type (an instant in time). The result of subtracting an interval from a DATE is also a DATE.
Instead, try this:
s.timeSubmitted >= ( NOW() - INTERVAL 60 DAY )
This gives you what you want, because NOW() returns a DATETIME, so the result of the subtraction is also a DATETIME.
INTERVAL 60 DAY is exact - your problem is that CURDATE() isn't. It returns whole days, not the current time.
Use NOW() instead!
I usually do
now()-interval 60 day
Assuming you want the same time of day 60 days ago;
s.timeSubmitted >= ( now() - interval 60 day);
Maybe an un-necessary note in this case; 1 day ago may be 23, 24 or 25 hours ago depending on DST changes, if you want a specific number of hours as an interval, don't use a day instead of 24 hours.
How can I subtract time in MySQL? For example, today is 16 March; I want to subtract 15 days to reach 1 March. Are there any methods that can be used to subtract 15 days from the current date?
SELECT DATE(NOW()-INTERVAL 15 DAY)
For a list of units see http://dev.mysql.com/doc/refman/5.1/en/date-and-time-functions.html#function_date-add
Not entirely related to this question but is related to the title:
SELECT SUBTIME("10:24:21", "5"); -- subtracts 5 seconds. (returns "10:24:16")
SELECT SUBTIME("10:24:21", "01:00:00"); -- subtracts one hour. (returns "09:24:21")
Documentation: MySQL SUBTIME function
Use:
SELECT NOW() - INTERVAL 15 DAY
to keep the datetime precision.
You can use this :
SELECT DATE(NOW()-INTERVAL 15 DAY);
for when you want to subtract the number of days.
In order to subtract the time instead, say 15 minutes, the following should work:
SELECT(DATE_SUB(NOW(), INTERVAL '15:0' MINUTE_SECOND));
Adding the reference link again :- https://dev.mysql.com/doc/refman/8.0/en/date-and-time-functions.html#function_date-add.
Yes its possible using date function in Mysql
select distinct
lastname,
changedat, date_add(changedat, interval -15 day) as newdate
from employee_audit;
lastname and changedat is field name and employee_audit is table name.
I have subtract 15 days from my date - check image please. thanks