How to merge 2 queries to work with pagination? - laravel

Question

I currently have a query that sums the number of non-active users in the last year and groups them by country and city and then paginates the result:
UserData::query()
->select(
country,
city,
DB::raw('SUM(CASE WHEN end_date IS NULL THEN 0 ELSE 1 END) AS not_active'),
)
->whereBetween('created_at', [Carbon::now()->subYear(), Carbon::now()])
->groupBy('country', 'city')
->paginate('500');
But I also need to add to each group a column that shows how many active users are of the same group, of all time, not just last year:
UserData::query()
->select(
country,
city,
DB::raw('SUM(CASE WHEN end_date IS NULL THEN 1 ELSE 0 END) AS active'),
)
->groupBy('country', 'city')
->get();
Then in the frontend I want to display the data in a table so I want the data to be "merged" so that I can output the matching active and not_active columns together, so the end result should look like that:
country | city | active(all time) | not active(past year)
------------|-----------|------------------|-----------------------
Sweden | Stockholm | 25 | 1
Switzerland | Bern | 43 | 13
But how can it be done when using pagination?
I tried to do it with subqueries but that didn't work: (Note that I am using slightly different query checking whereNull for active users and whereNotNull for non-active users:
$result = UserData::select('end_date', 'country', 'city')
->where(function ($query) {
$query->select('end_date')
->whereNull('end_date')
->whereBetween('created_at', [Carbon::now()->subYear(), Carbon::now()]);
}, 'active')
->where(function ($query) {
$query->select('end_date')
->whereNotNull('end_date')
}, 'not_active')
->groupBy('country', 'city')
->paginate('500');

Answer 1

This can be solved by using a union()
$first = UserData::query()
->select(
'country',
'city',
DB::raw('SUM(CASE WHEN end_date IS NULL THEN 0 ELSE 1 END) AS not_active'),
)
->whereBetween('created_at', [now()->subYear(), now()]);
$second = UserData::query()
->select(
'country',
'city',
DB::raw('SUM(CASE WHEN end_date IS NULL THEN 1 ELSE 0 END) AS active'),
);
$first->union($second)
->groupBy('country', 'city')
->paginate('500');
Which will execute a SQL union query like select *cols* from *table* where *clause* union (select *cols* from *table* where *someOtherClause*)