This question already has an answer here:
Closed 11 years ago.
Possible Duplicate:
trying to get the number of months
I have a
memberpayments table
totalamountpaid
exppayments
expmonthly payments
dueday
memberid
I want to find the datediff like this way here I have found the date diff using c#
but I want to find the date diff using mysql
double equivalentPayments = totalamountpaid /expmonthly payments;
double monthdiff = Math.Ceiling(exppayments - equivalentPayments);
monthdiff -= 1;
int dueDay = 01;
DateTime expDate = DateTime.Today.AddMonths((int)monthdiff).AddDays(DateTime.Today.Day - dueDay);
int diff = DateTime.Today.Subtract(expDate).Days;
I have tried using Date diff but it was giving the difference between two dates and it was not giving datediff like above solution(c#).
can i get these statements all in one query......using mysql....
would any one pls help me out
MySQL have a large set of date time functions. Finding differences between dates are fairly trivial using them :)
http://dev.mysql.com/doc/refman/5.5/en/date-and-time-functions.html
If i understand correctly, all you are after is the difference in days between two dates. This can be done with DATEDIFF(a,b) :)
Related
I need to get number of days between 2 dates, a given one and current date.
But in pure SQL, I mean without usign functions, it is possible?
For exaple
SELECT days (t.givenDate) - days (current date) FROM table t
Have you any idea?
Thaks a lot.
The built-in function is datediff(). The equivalent for the above is:
SELECT datediff(t.givenDate, curdate()) FROM table t;
Normally, givenDate would be in the past and you would want the arguments in the other order.
This question already has answers here:
How to get first day of every corresponding month in mysql?
(15 answers)
Closed 5 years ago.
Let's say that I have an input date of "2017-01-31" or "2017-02-28". I want to take this input date and make SQL change it to "2017-01-01" or "2017-02-01".
Is there a way to do this via MySQL functions in a query?
Several ways to do that. My preference is to use DATE_FORMAT to replace the day portion with constant 01.
SELECT DATE_FORMAT('2017-01-31','%Y-%m-01') + INTERVAL 0 DAY AS dt
There are lots of ways to skin that cat.
For example, we could subtract the integer number of days minus 1 ...
SELECT '2017-01-31' + INTERVAL 1-DAY('2017-01-31') DAY
(With the second form, the date value needs to be supplied twice. With the first, we only need to supply the value one time. I think the first form is easier for a future reader to understand... pretty clear what the author is intending.)
Use your date instead of my example:
SELECT CONCAT_WS('-',YEAR('2017-01-28'),MONTH('2017-01-28'),'01')
This question already has answers here:
ROW_NUMBER() in MySQL
(26 answers)
Closed 8 years ago.
I have a table that tracks the activity in several websites. Each row is of the following form: (Date, Hour, Website, Hits)
The Hour field is a number between 0 and 23 and represents an entire hour (for example, 22 is for any hits between 22:00 and 22:59).
I want to find the overall slowest hour for each website, meaning the input should be something like (Website, Hour).
In order to do that, I was thinking I should have a nested query to find the minimum hits for each website on each day, and then count the values of Hour (again, for each website on each day), and see which value is the maximal.
I'm still new to SQL so I'm having difficulties using the min() function properly, to find the minimal value only for a specific date and website. Then I have the same problem with using count() for a specific website.
I'm also curious if I can get not just the most common slowest hour, but maybe the 3 slowest, but at least to me it seems like it's really complicating the problem.
For the first nested query, I considered something like this:
SELECT DISTINCT Date Date_t, Website Website_t, Hour,
(SELECT min(Hits) from HITS_TABLE WHERE Date=Date_t and Website=Website_t) as MinHits
FROM HITS_TABLE
But not only it takes an abnormally long time to calculate, it also gives me multiple entries of (Date_t, Website_t, Hour, min(Hits)) for each value of Hour, so I take it that I'm not doing it in the smartest, nor the most efficient way.
Thanks in advance for any help!
You can get the minimum hour using a trick in MySQL:
select website, substring_index(group_concat(hour order by hits), ',', 1) as minhour
from table t
group by website;
For each website, this constructs a comma-delimited list of hours, ordered by the number of hits. The function substring_index() returns the first row.
This is something of a hack. In most other databases, you would use window/analytic functions, but these are not available in MySQL.
EDIT:
You can do this in standard SQL as well:
select t.*
from table t
where not exists (select 1
from table t2
where t2.hour = t.hour and
t2.hits < t.hits
);
This is interpreted as: "Get me all rows from the table where there are no other rows with the same hour and a lower number of hits." This is a round-about way of saying: "Get me the hour with the minimum value." Note that this will return multiple rows when there are ties.
This question already has an answer here:
MySQL - Thousands separator
(1 answer)
Closed 9 months ago.
I have a query:
select sum(invoiceamount) as invoice
from fact_salescount
where year in ({YEAR})
and month >= ({FROMMONTH})
and month <= ({TOMONTH})
This query can return a value from 100.00 to 15034115.93. It will return ONE value.
I would like to add, for each 000, like this: 15,034,115.93
I've seen a lot of similar questions, but none match mine. I hope someone can help me out.
I am using Pentaho and MySQL, and creating these queries within the Design Studio.
SELECT FORMAT(sum(invoiceamount),2)
FROM fact_salescount
WHERE year IN ({YEAR})
AND month >= ({FROMMONTH})
AND month <= ({TOMONTH})
This should do what you want, but I still don't like formatting number in the backend.
This question already has answers here:
Closed 11 years ago.
Possible Duplicate:
Select by Month of a field
i want to get the data from database whose month is 7. means
My Date format is
PostDate datetime
now i want to query..
select * from tabelname where PostDate = 7
If you are asking how to query MySQL for date objects based on month, then this may be your answer.
select * from tablename where month(PostDate) = '07';
Keep in mind this function (month()) is MySQL specific.