MYSQL query relut based on cuttent time - mysql

Query to get list of records between stating time and end time
Ex:
Start_time End_time
----------------------
22:00 05:00
20:00 02:00
If i query in between the time have to get those result am not using any date specific. i used Now() Between not worth any one have good idea

Try to use DATE_FORMAT(dt,'%H:%i') to get HH:MI string from date and then compare it with start_time and end_time depend on start_time>end_time or not.
SET #start_time = '22:00';
SET #end_time = '05:00';
select *
from T
where (
(#start_time<=#end_time)
AND (DATE_FORMAT(dt,'%H:%i') >= #start_time)
AND (DATE_FORMAT(dt,'%H:%i') <= #end_time)
)
OR
( (#start_time>#end_time)
AND
(
(DATE_FORMAT(dt,'%H:%i') >= #start_time)
OR
(DATE_FORMAT(dt,'%H:%i') <= #end_time)
)
);
SQLFiddle demo

Related

dividing datetimes by date

I save my news in db and each news have an field that save it's datetime in format:
xxxx-xx-xx xx:xx:xx
and now I want retrieve news by date xxxx-xx-xx and for example today what I must write in where of my sql code
It's very simple:
SELECT *
FROM tableName
WHERE DATE( datetime_field ) = DATE( NOW( ) )
please notice that DATE() return only date value and NOW() return current datetime
use DATE function. eg
SELECT *
FROM tableName
WHERE DATE(columnName) = '2012-12-20'
this will retrieve all records where date is December 20, 2012.
select *
from TableName
where
DATE_FORMAT(columnName,'%m-%d-%Y') = '01-01-2012'

MySQL query: get data in specific interval

I have a MySQL Table with one datetime column. I want to prevent that the PHP-script gets to much data. So i'm searching for a solution that a MySql query only selects rows which have a distance of 1 minute or whatever. is there something simple or do i have to code a for-loop with a new mysql query every time.
Example
timestamp
2012-09-25 00:00:00-->
2012-09-25 00:00:50
2012-09-25 00:01:23
2012-09-25 00:01:30-->
2012-09-25 00:02:33
2012-09-25 00:02:40
2012-09-25 00:03:01-->i want those
thanks in advance
Try this :
SELECT create_time
FROM timeTable
WHERE create_time
IN (
SELECT min( create_time )
FROM timeTable
GROUP BY FROM_UNIXTIME( UNIX_TIMESTAMP( create_time ) - MOD( UNIX_TIMESTAMP( create_time ) , 60 ) );
How it works :
i) Groups the table by datetime rounded to the interval, 1 minute (60 seconds) here.
ii) Gets the top row from each group.
This can be a good sampling criteria for your data.
This query can be optimized alot on these points:
i) Put a where clause for a date = REQUIRED DATE, and then do other operations on hour+minutes instead of whole datetime.
ii) If your interval is 1 minute, then substring of the timestamp or date_format can be tried too to round it off to nearest minute.
eg.
SELECT create_time
FROM timeTable
WHERE create_time
IN (
SELECT min( create_time )
FROM timeTable
GROUP BY DATE_FORMAT( `create_time` , 'Y-M-D %H:%i' )
);
Try this
SET #time := '1000-01-01 00:00:00';
SET #interval := 60;
SELECT colDate
FROM table
WHERE TIMESTAMPDIFF( SECOND, #time, colDate ) >= #interval
AND #time := colDate
How it works.
#interval is the time difference desired between the current and previous colDate. The first parameter in TIMESTAMPDIFF determines the unit of time that the interval will use. ex: SECOND, MINUTE, HOUR, DAY, WEEK, MONTH, QUARTER, or YEAR.
#time keeps track of the previous colDate, and it is compared with the current row. If the difference between the previous and current colDate is equal to or greater than the interval, it is included.
WHERE timestamp LIKE '%:30:00%' will get you every 30 seconds..
But this will only work if you have uniform entries..if your timestamps dont all end evenly.. you'll need to let us know.
EDIT
I think you may be looking for this:
How do you select every n-th row from mysql

SQL Query for reservation dates that break a month end?

I'm using a custom PHP function to produce a visual calendar for a single month that blocks out dates based on a table that contains an start date, and an duration - For example:
...This is produced by data saying that the table should be blocked out for 4 days from the 14th, and 7 days from the 27th.
The query looks something like this:
SELECT GROUP_CONCAT(DATE_FORMAT(start_date,'%d'),':', event_duration) AS info
FROM events
WHERE YEAR(start_date = '2012'
AND MONTH(start_date) = '07'
ORDER BY start_date
(You could safely ignore the group concat and return the data as individual rows, that doesn't really matter).
I'm looking for a modification to the query that would block out dates at the start of the month IF an event starts in the previous month, but its length takes it into the following.
For instance - in the above example, the event on the 27th is actually scheduled to last 7 days in the database, so if I ran the query for MONTH(start_date) = '08' I'd like to say the first two dates blocked out, which they wouldn't currently be, because the start date that would block it out is not in the month being selected.
I'm fairly sure there's a subquery or something in there to grab the rows, but I just can't think of it. Any takers?
EDIT
The answer from Salman below pointed me in the directon I wanted to go, and I came up with this as a way of getting carryovers from the previous month to show as '1st' of the month with the number of remaining days:
SELECT IF(MONTH(start_date) < '08', '2012-08-01', start_date) AS starter,
IF(MONTH(start_date) < '08', duration - DATEDIFF('2012-08-01',start_date), duration) AS duration
FROM EVENTS
WHERE YEAR(start_date) = '2012'
AND (MONTH(start_date) = '08' OR MONTH(start_date + INTERVAL duration DAY) = '08')
Obviously a lot of variables there to replace in PHP, so maybe there's an even better way?
Original Answer:
Assuming that the month in question is 2012-07, you need this query:
SELECT column1, column2, columnN
FROM `events`
WHERE `start_date` <= '2012-07-01'
AND `start_date` + INTERVAL `duration` DAY > '2012-07-01'
ORDER BY start_date
Revised Answer:
Apparently you need a query that checks for overlapping (or conflicting) dates. The example dates are 2012-07-01 through 2012-08-01 and the query is:
SELECT *
FROM events
WHERE '2012-08-01' > start_date
AND start_date + INTERVAL duration DAY > '2012-07-01'
ORDER BY start_date
To constrain the start date and interval, you can use SELECT ... CASE statement:
SELECT
CASE
WHEN start_date < '2012-07-01' THEN '2012-07-01'
ELSE start_date
END AS start_date_copy,
CASE
WHEN start_date < '2012-07-01' THEN duration - DATEDIFF('2012-07-01', start_date)
ELSE duration
END AS duration_copy,
FROM ...
The answer I was looking for, thanks to the other contributor for pointing me in the right direction and enabling me to solve it!
This is based on $yyyy and $mm coming from PHP (in my case, into a function call), and selecting individual rows rather than grouping:
SELECT start_date, duration
FROM reservations
WHERE YEAR(start_date) = '".$yyyy."'
AND MONTH(start_date) = '".$mm."'
UNION
SELECT '".$yyyy."-".$mm."-01',
duration - DATEDIFF('".$yyyy."-".$mm."-01',start_date)
FROM reservations
WHERE YEAR(start_date) = '".$yyyy."'
AND MONTH(start_date) < '".$mm."'
AND MONTH(start_date + INTERVAL duration DAY) = '".$mm."'
ORDER BY start_date

SELECT all records that are 30 days old

I need to SELECT all records that are 30 days old. I have the code below but it's not working. In updatestatus I have dates like 12/26/2011. I create a 30 day old date like
$onemonthago="01/01/2012";
$sth = $dbh->prepare(qq(
SELECT *
FROM people
WHERE STR_TO_DATE (updatestatus,'%m/%d/%y')
<= STR_TO_DATE ( "$onemonthago",'%m/%d/%Y')
) );
If the datatype of updatestatus is date:
SELECT *
FROM people
WHERE updatestatus <= '2012-01-01'
or:
SELECT *
FROM people
WHERE updatestatus <= CURRENT_DATE() - INTERVAL 1 MONTH
If the datatype is datetime or timestamp and you want to check the time part, too:
SELECT *
FROM people
WHERE updatestatus <= NOW() - INTERVAL 1 MONTH
You can put an exact datetime instead of the NOW() - INTERVAL 1 MONTH. The correct way depends on how you are storing the datetimes or timestamps (does the Perl code or MySQL creates them in the first place?).
You could also put - INTERVAL 30 DAY which yield slightly different results.
This is what I used. Very simple
$sth = $dbh->prepare(qq(SELECT * FROM people WHERE updatestatus + INTERVAL 30 DAY <= NOW() )) or die $DBI::errstr;
If the time column is in timestamp then use below query.(use from_unixtime function)
SELECT wd.* FROM `watchdog` as wd
WHERE from_unixtime(wd.timestamp) <= NOW() - INTERVAL 1 MONTH
You can try this way. In SQL, there is dateadd function and I think there should be similar function in MySQL.
select *
from Table
where str_to_date between dateadd(day,-30,getdate()) and getdate()
It retrieve records between current date and past 30 days. You need to adjust for time. If you don't count time, you need to remove timestamp.

MySQL add 12 hours to a time field

I need to add 12 hours to a MySQL TIME field (not DATETIME) and I'm having trouble.
UPDATE `events`
SET start_time = DATE_ADD(start_time, INTERVAL 12 HOUR)
WHERE `start_time` < '11:00:00'
returns with no errors but doesn't change anything, I think because start_time is a TIME field.
UPDATE `events`
SET start_time = start_time + '12:00:00'
WHERE `start_time` < '11:00:00'
adds 12 seconds.
Try using ADDTIME instead of DATE_ADD. You could do SET start_time = ADDTIME(start_time, '12:00:00')
UPDATE `events`
SET start_time = start_time + INTERVAL 12 HOUR
WHERE `start_time` < '11:00:00'
The MySQL functions that accept INTERVAL arguments are mostly unnecessary; you can just add and subtract intervals with + and -.
set start_time = ADDTIME(start_time,'12:00:00')
DATE_ADD works fine with timestamp etc, but not with TIME
update my_table SET modified_date = ADDTIME(scheduled_date, '03:15:00')
This will add 3 hours , 15 minutes in modified_date
if the developer does not want to update data and wants to add hours or minutes to time. It can be done following way:
The developer can use an AddTime() function to add hours to time column in MySQL.
It can be used like below way:
AddTime(COLUMN,’01:00:00′) to add an hour in MySQL time column
AddTime(COLUMN,’00:01:00′) to add a minute in MySQL time column
sql query example:
select id,name,AddTime(login_time,'01:00:00') as login_time FROM `table`
First answer:
SET start_time = ADDTIME(start_time, '12:00:00')
Will only work if start_time is less than 12 hours.
If start_time is for example 13:00:00, then the end result will be 25:00:00, to get 01:00:00, you can use the following trick:
SET start_time = DATE_FORMAT(ADDTIME(CONCAT('1970-01-01 ', start_time), '12:00:00'), '%H:%i:%s')
(I used this to correct for the timezone)