How to pull out the same name value from two different tables and operate with it?

Question

MySQL

Good day.
There are two different tables "Purchases" and "Sales", they have the same column, you need to take its values ​​and manipulate it, how can this be done?

Answer 1

// Если созданы модели
$sales = Sales::find(1);
$purchases = Purchases:find(1);
$sales_column = $sales->any_column;
$purchases_column =  = $purchases->any_column; 

manipulation($sales_column , purchases_column );

$sales->update();
$purchases->update();

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