Selecting from multiple tables in laravel - laravel

Question

please help.I have a test booking table that looks like this
Schema::create('test_bookings', function (Blueprint $table) {
$table->unsignedInteger('RequestID');
$table->string('bookingDate');
$table->string('timeSlot');
$table->unsignedInteger('nurse_id');
$table->timestamps();
});
and a tests table that looks like this
Schema::create('tests', function (Blueprint $table) {
$table->unsignedInteger('RequestID');
$table->unsignedInteger('patientID');
$table->string('barcode');
$table->string('temperature');
$table->string('pressure');
$table->string('oxygen');
$table->unsignedInteger('nurseID');
$table->timestamps();
});
I want to show the RequestID,bookingDate,timeSlot, name and surname of the nurse only if the test_bookings RequestID is in tests table. This is my nurse table
Schema::create('nurses', function (Blueprint $table) {
$table->unsignedInteger('nurseID');
$table->string('name');
$table->string('surname');
$table->string('idNumber');
$table->string('phone');
$table->string('email');
$table->unsignedInteger('suburb_id');
$table->timestamps();
$table->index('suburb_id');
});
This is the code that i tried
$tests = DB::table('tests')
->select('RequestID','bookingDate','timeSlot','name','surname')
->join('nurses','nurses.nurseID','test_bookings.nurse_id')
->join('test_bookings','test_bookings.RequestID','=','tests.RequestID')
->get();

Answer 1

but when I join the tests table nothing is showing
that because you are using join clause that generate innerJoin statement, and to see the results you should use leftJoin
$tests = DB::table('tests')
->select('RequestID','bookingDate','timeSlot','name','surname')
->leftJoin('nurses','nurses.nurseID','=','test_bookings.nurse_id')
->leftJoin('test_bookings','test_bookings.RequestID','=','tests.RequestID')
->get();

Answer 2

Why you're not using ORM here, a simple one-to-one relationship can do the job perfectly. Here is an example:
class TestBooking extends Model {
# Other code...
public function nurse(){
return $this->belongsTo(Nurse::class);
}
}
class Test extends Model {
# Other code...
public function testBooking(){
return $this->belongsTo(TestBooking::class, 'RequestID','RequestID');
}
}
Now you can get all data like this:
$tests = Test::with("testBooking","testBooking.nurse")->get();
// and get data inside loop like this:
$test->RequestID // to get request ID
$test->testBooking->bookingDate // to get booking date
$test->testBooking->timeSlot // to get timeSlot
$test->testBooking->nurse->name // to get nurse name
$test->testBooking->nurse->surname // to get nurse surename
To know more about relationships read documention.