php - 如何计算 pf 以及如何显示 pf 总量

Question

这里我要计算PF，我们每个月都要扣pf，现在我要显示pf的总金额，这是我的数据库表结构

id    first_name   pf_amount   pf_month    badge_number

1      Kani         200         01-2017      01

2      Mahesh       250         01-2017      02

3      Kani         200         02-2017      01

4      Mahesh       250         02-2017      02

在我的列表页面中，我想显示 badge_number (01) 有 400 和 badge_number (02) 有 500。这里 badge_number 是唯一的

我这样写了查询，但在这里我得到了所有数据，如何根据我的要求做

$check = mysql_query("SELECT * FROM pf_history");
while($row = mysql_fetch_array($check)) {
   echo $row['pf_amount'];
}

Answer 1

在查询中使用 GROUP BY AND SUM():

SELECT first_name, pf_month, SUM(pf_amount) as total FROM pf_history GROUP BY badge_number

代码:

$check = mysqli_query("SELECT first_name, pf_month, SUM(pf_amount) as total FROM pf_history GROUP BY badge_number");
while($row = mysqli_fetch_array($check)) {
  echo $row['total'];
}

group by 和 sum() 的

引用:

GROUP BY

SUM()