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MySQL Query for certain date range

Tags:

date

mysql

i'm having the following table data:

Table: Seasons                
id   from        to
---------------------------
1    2013-08-30  2013-09-04
2    2013-09-05  2013-09-08
3    2013-09-09  2013-09-20

i need to run a query which returns all records which are within a certain date range, for example: return all records which are affected from 2013-09-04 to 2013-09-05

it would be like

date  range:                    | 09-04 - 09-05| 
seasons:          08-30 - 09-04 | 09-05 - 09-08     | 09-09 - 09-20

so it should return the first 2 records. i've tried the query with BETWEEN but it seams i need to build up several cases - or is there a simpler way? thankx

like image 981
Fuxi Avatar asked Sep 03 '13 23:09

Fuxi


2 Answers

It's amazing no one has noticed this for almost two years, but the other answers are all wrong because they didn't take into account the case when both the start date and the end date fall beyond the scope of the search range. Consider this is the range of the date:

start_date <<---------------------------- date range --------------------------->> end_date

And this is the range of our search:

start_date <<---------------------------- date range --------------------------->> end_date

                 start_search <<-------- search range -------->> end_search

The search should give us a positive result because they intersect. But if you use the other answers, you would get a negative result because neither start_date nor end_date is between start_search and end_search.

To get the solution, let's draw all 4 possible modes of intersection:

                  start_date <<---------- date range --------------------------->> end_date

start_search <<------------------------- search range -------->> end_search
start_date <<---------------------------- date range ---------->> end_date

               start_search <<---------- search range ------------------------>> end_search
start_date <<---------------------------- date range --------------------------->> end_date

                 start_search <<-------- search range -------->> end_search
                 start_date <<----------- date range -------->> end_date

start_search <<------------------------- search range ------------------------>> end_search

You can OR all 4 possible cases to obtain the straightforward solution:

select*from table where

   /* 1st case */ start_date between start_search and end_search         
or /* 2nd case */  end_date  between start_search and end_search         
or /* 3rd case */ (start_date <= start_search and end_date >= end_search)
or /* 4th case */ (start_date >= start_search and end_date <= end_search)

/* the 4th case here is actually redundant since it is being covered by the 1st and 2nd cases */

A less straightforward solution is:

select*from table where

    start_date  between start_search and end_search /* covers 1st and 4th cases */          
or start_search between  start_date  and  end_date  /* covers 2nd and 3rd cases */

Try to visualize it using the diagrams above.


If we attempt to extrapolate a pattern out of the 4 diagrams above, we can see that during an intersection, end_date is always >= start_search, and on the flip side, start_date is always <= end_search. Indeed, visualizing further, we can see that when those two conditions hold, we cannot not have an intersection.

As such, another solution is as simple as:

select*from table where

end_date >= start_search && start_date <= end_search

And the advantage of this solution is that we only need 2 comparisons. Contrast that with the "OR everything" approach which requires from 2 up to as much as 8 (3 &plus; 3 &plus; 2) comparisons. (Each between call consists of 3 comparisons.)

like image 128
Pacerier Avatar answered Sep 30 '22 13:09

Pacerier


Try with:

SELECT *
FROM `Seasons`
WHERE (`from` BETWEEN '2013-09-04' AND '2013-09-05' OR `to` BETWEEN '2013-09-04' AND '2013-09-05')
like image 43
Juan M Avatar answered Sep 30 '22 13:09

Juan M