How to fetch users who does not have reports for 6 consecutive months using laravel? - laravel

Question

I'm developing a report system, and I want to fetch users who did not report for six (6) consecutive months. How do I achieve this?
I've tried the code below but I'm not getting the desired output. There is also a problem. Let's say the date interval is 12 months. How can I determine if there is no report for 6 consecutive months?
$dateStart = '2018-10-31';
$dateEnd = '2019-03-31';
$intervals = Carbon::parse($dateStart)->diffInMonths($dateEnd);
$users = $users->whereDoesntHave('reports', function($query) use($intervals) {
for ($i = 5; $i >= 0; $i--) {
$firstMonth = Carbon::parse($dateEnd)->subMonthsNoOverflow($intervals);
$query->where('date', '>=', $firstMonth->format('Y-m-d'))->where('date', '<=', $dateEnd);
}
});

Answer 1

What I will do is that I will create a loop per month based on the start and end date, then check if he did not have a report for that month. If it doesn't have a report for that month, I will increment a counter, and if that counter reaches 6 counts, exit the loop and the condition was satisfied.
Below is the basic idea:
$dateStart = '2018-10-31';
$dateEnd = '2019-10-31';
$count = 0;
$no_report_for_6_consecutive_months = 0 ;
startloop
$have_report = Model::whereMonth('date_column', $date_of_loop->format('m'))->get();
if($have_report->count()){
$count = 0;
}
else{
$count++;
}
if($count==6){
$no_report_for_6_consecutive_months = 1 ;
break;
}
endloop

Answer 2

You have to find distinct users who report for six (6) consecutive and get difference with all users.
$enddate = 2019-04-15;
$startdate = date("Y-m-d", strtotime("-6 months", strtotime($enddate)));
$users = User::all();
$usersIdArray = $users->pluck("id")->all();
$reportedBy = Report::where('date', '>=', $startdate)
->where('date', '<=', $enddate)
->distinct("user_id")->get();
$reportedByIdArray = $reportedBy ->pluck("id")->all();
$notReportedByIdArray = array_values(array_diff($usersIdArray , $reportedByIdArray));
$notREportedUsers = User::whereIn(id", $notReportedByIdArray)->get();
//its a way but not tested

Answer 3

I have modified the query from this answer
I believe the query can be wrote cleaner. I will let you do this if you want to.
App\User::select('*')
->from(\DB::raw("(select
low.*,
low.`date` as date_start,
high.`date` as date_end,
to_days(high.`date`) - to_days(low.`date`) as day_gap,
period_diff(date_format(high.`date`, '%Y%m'),
date_format(low.`date`, '%Y%m')) as month_gap
from reports low, reports high
where high.`date` =
(select
min(`date`)
from reports
where
`date` > low.`date`
and low.user_id = high.user_id
)
) as d")
)->get();
Now you will get all the users with 4 extra fields: date_start; date_end, day_gap and month_gap
If you want the users with a month gap of 6 months you can do this:
App\User::select('*')
->from(\DB::raw("..."))
->where('month_gap', '>=', 6)
->get();