In Laravel 9, query the value of a single row and a column

1. When there are multiple rows of data in the table, the implementation is as follows. Error: call to a member function value() on null. as shown in Figure 1

Figure 1

$return = Order::query()
	->select('id')
	->where('transaction_no', '=', '1')
	->first()
	->value('id');
var_dump($return);
exit;

2. The adjustment is realized as follows. When the record does not exist, the query result is NULL. When the record exists, the query result is int(6), which is the single-column value of the first record. in line with expectations.

$return = Order::query()
	->select('id')
	->where('transaction_no', '=', '1')
	->limit(1)
	->value('id');
var_dump($return);
exit;

3. Check the execution sql, which is in line with expectations. as shown in Figure 2

Figure 2

select `id` from `orders` where `transaction_no` = '1' limit 1