Query builder filter based on related records sum

Question

I would appreciate some help regarding laravel/octobercms query builder. I have two models/tables as follows:

CV model has many Experiences, Experience model belongs to CV.

CVs table  
| id | user_id |  
| --- | ------ |  
| 1 | 11 |  
| 2 | 22 |  



Experiences table  
| id | cv_id | from | to |  
| --- | ------ | ----- | --- |  
| 1 | 1 | 2019-01-01 | 2020-01-01 |  
| 2 | 1 | 2020-05-02 | 2021-09-01 |   
| 3 | 2 | 2019-01-01 | 2019-05-01 |  
| 4 | 2 | 2020-01-01 | 2021-05-01 |   

I'm trying to use query builder to filter CV's based on Experiences duration. For example, CV with id: 2, has two experiences with id 3 and 4, each with 4 moths of experience, so in total CV with id: 2 has 8 months of experience.

So far I tried variations of:

$query = Cv::query()->whereHas('experiences', function ($query) {
        $query->addSelect(DB::raw("SUM(DATEDIFF(COALESCE(`to`, CURDATE()), `from`)) AS sum_experience"));
    });

Above produces:

select * from `cvs` where exists (select *, SUM(DATEDIFF(COALESCE(`to`, CURDATE()), `from`)) AS sum_experience from `cv_expriences` where `cvs`.`id` = `cv_expriences`.`cv_id`)

But I don't know how can I compare sum_experience value, to a value I need. Any help is appreciated.

Answer 1

It would be great if you can just calculate experience in a month while adding/updating records of the Experiences table and add it directly to the CV table .

It will make things really easy for you to manage and search from it as well as less complex DB queries will increase response time

if any doubt please comment.