如何检查给定的日期段在MySQL和PHP中的两个日期之间

Question

I have a travel history of the employee. I want to check, for the particular month, whether he is in outstation (traveled outside) or in the office, to calculate number of hours in travel. Just we are maintaining the travel database, in that we entered employee name with client place traveled with travel date and returned date.

One employee have the following data:

• Traveled date: '2015-08-29' (29th Aug 2015)
• returned date: '2015-11-06' (6th Nov 2015)

So here, I want to check in the month of October, all employees that are out of the office. Obviously this guy should come in that category, but I could not get him.
I also tried directly in MySQL workbench, but I didn't get the result.

My original PHP code:

// $req['date_start'] = '2015-10-01'
// $req['date_end'] = '2015-10-31'

$employeeTravel = new EmployeeTravelRecord();
$TravelEntryList = $employeeTravel->Find("(travel_date between ? and ? or  return_date between ? and ? )",array($req['date_start'], $req['date_end'],$req['date_start'], $req['date_end']));
$startdate = $req['date_start'];
$enddate = $req['date_end'];
foreach($TravelEntryList as $Travelentry){
    $key = $Travelentry->employee;  

    if($startdate >= $Travelentry->travel_date)
    {
        $firstdate = $startdate;
    }
    else
        $firstdate = $Travelentry->travel_date;

    if($enddate <= $Travelentry->return_date )
    {
        $lastdate = $enddate;
    }
    else
        $lastdate = $Travelentry->return_date;

    $holidays = $this->getholidays($firstdate,$lastdate);
    $totalhours = $this->getWorkingDays($firstdate,$lastdate,$holidays); //It returns in total time of outstation in hours excluding company holidays
    $amount = $totalhours;
    if(isset($TravelTimeArray[$key])){
        $TravelTimeArray[$key] += $amount;
    }else{
        $TravelTimeArray[$key] = $amount;
    }
}

But my input data doesn't retrieve that particular employee record, because both traveled date and returned date don't fall in my input dates.

MySQL Workbench:

SELECT * FROM employeetravelrecords where travel_date between '2015-10-01' and '2015-10-31' or  return_date between '2015-10-01' and '2015-10-31';

I got only the following result:

+----+----------+---------------+----------------+----------+------------------+------------------+----------------+
| id | employee | type          | project        | place    | travel date      | return date      | details        |
+----+----------+---------------+----------------+----------+------------------+------------------+----------------+
| 13 | 38       | International | PVMTC Training | Hongkong | 11/10/2015 13:33 | 28/11/2015 13:33 | PVMTC Training |
| 14 | 48       | International | PVMT           | VIETNAM  | 10/10/2015 9:28  | 1/1/2016 9:28    | PETRO          |
| 17 | 57       | International | PVMT           | Saudi    | 10/10/2015 11:39 | 2/1/2016 11:39   |                |
+----+----------+---------------+----------------+----------+------------------+------------------+----------------+

The following record didn't get retrieved by this query:

+---+----+---------------+------+-----+-----------------+-----------------+-----------------+
| 7 | 22 | International | MOHO | XYZ | 29/8/2015 18:00 | 6/11/2015 18:00 | FOR DDS review  |
+---+----+---------------+------+-----+-----------------+-----------------+-----------------+

Answer 1

SELECT * FROM employeetravelrecords
WHERE
        return_date >= '2015-10-01' /* start parameter */
    and travel_date <= '2015-10-31' /* end parameter */

The logic seems a little mind-bending at first and I've even reordered the comparisons a little from my original comment above. Think of it this way: you need to return after the start of the range and leave before the end of the range in order to have an overlap.

For a longer explanation and discussion you might find this page useful: TestIfDateRangesOverlap

Answer 2

SELECT '2015-08-29' < '2015-10-31' AND '2015-11-06' >= '2015-10-01' on_leave;
+----------+
| on_leave |
+----------+
|        1 |
+----------+

Answer 3

You can use between for get data between two dates. Here is the working example.

Here is my table structure :

Table User

 user_id    user_name   created_date            modified_date
 1          lalji nakum 2016-01-28 17:07:06     2016-03-31 00:00:00
 2          admin       2016-01-28 17:25:38     2016-02-29 00:00:00

And here is my mysql query :

Query

SELECT * FROM `user` WHERE created_date between '2015-12-01' and '2016-12-31' or modified_date between '2015-12-01' and '2016-12-31'

Result of above query :

Result

user_id     user_name   created_date            modified_date
 1          lalji nakum 2016-01-28 17:07:06     2016-03-31 00:00:00
 2          admin       2016-01-28 17:25:38     2016-02-29 00:00:00

Answer 4

You want to find all those people who are not available for the complete duration say between T1 & T2 (and T2 > T1). The query you used will only give users whose start date and return date both lie between the given interval which is not the required output.

So to get the desired output you need to check for all employees who have started their journey on or before T1 and return date is on or after T2 (thus unavailable for complete interval [T1, T2]). So the query you can use is:

SELECT * FROM employeetravelrecords where travel_date <= '2015-10-01' and return_date >= '2015-10-31';

If you want employees who are even partially not available between the given duration then we need employees who started their travel before T1 and have any return date later than T1 (thus making them atleast unavailable for a part of the given interval):

SELECT * FROM employeetravelrecords where travel_date <= '2015-10-01' and return_date > '2015-10-01';