We have a table which we record our students' attendances in. We need to find out which students missed n number of contacts in a row.
Here is the attendance table structure with example records
----------------------------------------------------
| id | student_id | class_id | checkedin_time |
--------------------------------------------------
| 1 | 1 | 1 | null |
| 2 | 1 | 2 | 2019-07-09 10:30 |
| 3 | 1 | 3 | null |
| 4 | 1 | 4 | null |
| 5 | 1 | 5 | 2019-07-12 12:00 |
----------------------------------------------------
What I'm looking for is a code that show me records with id 3 and 4 (two subsequent missed contacts) grouped by student_id
This was my starting point:
$attendances = \App\Attendance::where('checked_time' , null)->get();
$attendances->groupBy('student_id')
Related
I have 2 table duty_sheets
centerId | centerName | p1 | p2 | p3 | p4 | ...p22 | examiId
1 | xyz | 1 | 5 | 8 | 7 | 1 | 1
2 | abc | 9 | 1 | 6 | 6 | 1 | 1
and feedback
id | centerId | inspectorId | A | B | C | examiId
1 | 1 | 1 | 1 | 5 | 8 | 1
2 | 2 | 9 | 9 | 1 | 6 | 1
here is my code
$center = DutySheet::select('duty_sheets.centerId', 'duty_sheets.centerName','feedback.id')
->leftJoin('feedback', function ($leftJoin) {
$leftJoin->on('duty_sheets.examId', 'feedback.examId')
->where("duty_sheets.centerId", 'feedback.centerId')
->where("feedback.inspectorId", 1);
})
->where("duty_sheets.examId", 1)
->where("p20", 1)
->get();
dd($center);
to retrieve "All rows from DutySheet where p20 = 1 and dutysheet.examId = 1, and relevant rows from feedback depend on centerId, inspectorId and examId.
The problem is that the query return feedback.id as null while the record exist in feedback table with the ids.
Laravel version = 9
The problem is in left Join
->where("duty_sheets.centerId", 'feedback.centerId')
This build a where against the value 'feedback.centerId'
duty_sheets.centerId='feedback.centerId'
You need use
->on("duty_sheets.centerId",'=', 'feedback.centerId')
Or
->whereColumn("duty_sheets.centerId", 'feedback.centerId')
Suppliers table
id | name
1 | supplier1
2 | supplier2
Products table
id | name
1 | product1
2 | product2
Attributes table
id | name
1 | width
2 | heigh
3 | weight
4 | volume
supplier_product table
supplier_id | product_id | price
1 | 1 | 1000
1 | 2 | 1500
2 | 1 | 1100
attribute_product
supplier_id | product_id | attribute_id | value
1 | 1 | 1 | 10
1 | 1 | 2 | 15
1 | 1 | 3 | 20
1 | 2 | 1 | 11
1 | 2 | 2 | 16
2 | 1 | 1 | 10
2 | 1 | 2 | 13
How to get attribute for each product for each supplier?
You can use the hasManyThrough relationship (https://laravel.com/docs/7.x/eloquent-relationships#has-many-through) as long as you modify the structure of your tables.
Supplier Model
public function attributes()
{
return $this->hasManyThrough('App\Attribute', 'App\Product');
}
I just want to ask on how to create an LINQ code that can fill up my html table.
Please look at my Tables below
Table EMP: note* my "Male" is boolean
+----+---------------+--------+--------+
| id | Male| JS_REF |DEPT_ID | POS_ID |
+----+---------------+--------+--------+
| 1 | 1 | 1 | 2 | 3 |
| 2 | 0 | 2 | 2 | 3 |
| 3 | 1 | 3 | 1 | 2 |
| 4 | 1 | 2 | 4 | 2 |
| 5 | 1 | 1 | 5 | 5 |
| 6 | 0 | 4 | 6 | 1 |
| 7 | 1 | 1 | 1 | 1 |
| 8 | 0 | 2 | 2 | 3 |
+----+---------------+--------+--------+
Table:JOB_STATUS
+----+--------------------+
| id | JS_REF| JS_TITLE |
+----+--------------------+
| 1 | 1 |Undefined |
| 2 | 2 |Regular |
| 3 | 3 |Contructual |
| 4 | 4 |Probationary|
+----+--------------------+
Table:DEPTS
+----+--------------------+
| id | DEPT_ID| DEPT_NAME |
+----+--------------------+
| 1 | 1 |Admin |
| 2 | 2 |Accounting |
| 3 | 3 |Eginnering |
| 4 | 4 |HR |
+----+--------------------+
Table: POSITIONS
+----+--------------------+
| id | POS_ID| DEPT_NAME |
+----+--------------------+
| 1 | 1 |Clerk |
| 2 | 2 |Accountant |
| 3 | 3 |Bookeeper |
| 4 | 4 |Assistant |
| 5 | 5 |Mechanic |
| 6 | 6 |Staff |
+----+--------------------+
I'd made a static table on what will be the outcome of the LINQ code
Here's the picture:
Here's what i've tried so far:
SELECT tb.DEPT_NAME,TB.JS_TITLE, TB.Male, TB.Female, (TB.Male + TB.Female) AS 'Total Employees' FROM
(
SELECT JS_TITLE,DEPT_NAME,
SUM(CASE WHEN MALE = 1 THEN 1 ELSE 0 END) AS Male,
SUM(CASE WHEN MALE = 0 THEN 1 ELSE 0 END) AS Female
FROM EMP
left join JOB_STATUS on JOB_STATUS.JS_REF = EMP.JS_REF
left join DEPTS on DEPTS.DEPT_ID = EMP.DEPT_ID
GROUP BY JS_TITLE,DEPT_NAME
) AS TB
ORDER BY CASE WHEN TB.MALE IS NULL THEN 1 ELSE 0 END
If anyone can help me or give me some tips on how can I implement this im stuck in this part.
101 is total count for male, 23 for female. (the values are just copy and pasted, that's why the values are the same)
(Actual data result)
I am trying to get the count of unique batches in gift_code table for each campaign. The gift_code table is joined to campaign table by campaign_id.
Here is some sample data for campaign table.
--------------+--------------
|campaign_id | name |
--------------+--------------
| 1 | abc |
--------------+--------------
| 2 | xyz |
--------------+--------------
Below is some sample data for gift_code table.
--------------+------------------------+--------------+
|gift_code_id | campaign_id | batch | unique_code |
--------------+-------------+----------+---------------
| 1 | 1 | 1 | zxc23 |
--------------+-------------+----------+--------------+
| 2 | 1 | 2 | rtc26 |
--------------+-------------+----------++-------------+
| 3 | 2 | 1 | z8723 |
--------------+-------------+----------+--------------+
| 4 | 2 | 2 | h7c26 |
--------------+-------------+----------++-------------+
| 5 | 2 | 2 | rrcf6 |
--------------+-------------+----------++-------------+
| 6 | 2 | 3 | r7y28 |
--------------+-------------+----------++-------------+
| 7 | 2 | 3 | bnc26 |
--------------+-------------+----------++-------------+
$campaign = DB::table('campaign')
->select('campaign.*', DB::raw('count(gift_code.batch) as batch_count')->groupBy('gift_code.campaign_id')->groupBy('gift_code.batch'))
->leftjoin('gift_code', 'campaign.campaign_id', '=', 'gift_code.campaign_id')
->get();
My expected results are:
--------------+-------------------------+
|campaign_id | name |batch_count|
--------------+-------------+-----------+
| 1 | abc | 2 |
--------------+-------------+-----------+
| 2 | xyz | 3 |
--------------+-------------+-----------+
Try below query
$data = \DB::table('campaign as c')
->leftJoin('gift_code as gc','c.campaign_id','=','gc.campaign_id')
->select('c.*',\DB::raw('COUNT(distinct(gc.batch)) as batch_count'))
->groupBy('c.campaign_id')
->get();
I have models Book and BookCategory
How do I select the cheapest book in every category?
Book table:
| id | name | price | book_category_id |
| 1 | test | 10 | 1
| 2 | test | 15 | 3
| 3 | test | 75 | 1
| 4 | test | 25 | 2
| 5 | test | 19 | 1
| 6 | test | 11 | 2
| 7 | test | 10 | 1
The selection should be :
| id | name | price | book_category_id |
| 1 | test | 10 | 1
| 2 | test | 15 | 3
| 6 | test | 11 | 2
I've tried:
$books = Book::groupBy("book_category_id")->orderBy("price")->get()
But the output is not the minimum price row.
any idea?
EDIT:
I found this page:
https://www.xaprb.com/blog/2006/12/07/how-to-select-the-firstleastmax-row-per-group-in-sql/
it has 90% of the solution in SQL
SELECT *
FROM books
WHERE price = (SELECT MIN(price) FROM books AS u WHERE u.book_category_id= books.book_category_id)
GROUP BY books.book_category_id
how to convert this to laravel query builder?
You need to perform a subquery like this post. Try this:
$books = Book::from(DB::raw("SELECT * FROM books order by price asc"))
->groupBy("book_category_id")->get();
Please note that this is a mysql only solution because in mysql you're allowed to not aggregate non-group-by columns. If you need to do this for another DB, you need to perform an inner join on the subquery