PHP：如何獲得變量列中的值的總和

Question

我試圖從表中獲得工資列的總和。我只需要回復總薪水。我試過了，

SELECT SUM(SalaryCol) FROM my_table;

我怎樣才能得到查詢結果作爲PHP變量？

Answer 1

SELECT SUM(SalaryCol) as total_salary FROM my_table; 

Answer 2

$sql = 'SELECT SUM(SalaryCol) as total_salary FROM my_table'; 

//$con is your connection variable 
$result=mysqli_query($con,$sql); 

while($row=mysqli_fetch_array($result,MYSQLI_NUM)){ 
    $salaries[] = $row['total_salary']; 
} 
return $salaries; 

然後你可以訪問此作爲數組，做任何

Answer 3

好吧，我理解了它自己。

$query = "SELECT SUM(SalaryCol) FROM my_table";

$sum = mysqli_fetch_row(mysqli_query($con, $query));

echo "Total : ".$sum[0];