Question

我正在尝试从数据库表中获取列的总和。但我得到的只是0.00。我的代码是：

$total_income_query = $db->prepare("select sum(credit) from accounts WHERE STR_TO_DATE(date, '%d/%m/%Y') BETWEEN STR_TO_DATE(:startDate, '%d/%m/%Y') AND STR_TO_DATE(:endDate, '%d/%m/%Y')");

$stmt->bindParam(':startDate',$startDate);
$stmt->bindParam(':endDate',$endDate);
$stmt->execute();

$total = $stmt->fetch(PDO::FETCH_NUM);

echo $total_income = $total[0];

它应该回应306700.80。我检查了查询。它在数据库中工作正常，但在我的PHP脚本中没有。它有什么问题？

Answer 1

编辑：我认为我的解释是错误的。但是仍然没有重新格式化数据库中的日期。那就是：我想你将日期存储在DATE / DATETIME

类型的列中

<?php
$total_income_query = $db->prepare("
    SELECT SUM(credit) 
    from accounts 
    WHERE date BETWEEN STR_TO_DATE(:startDate, '%d/%m/%Y') 
               AND STR_TO_DATE(:endDate, '%d/%m/%Y')");

$stmt->bindParam(':startDate',$startDate);
$stmt->bindParam(':endDate',$endDate);
$stmt->execute();

$total = $stmt->fetch(PDO::FETCH_NUM);

echo $total_income = $total[0];

Answer 2

好的，问题在于我的PDO代码。我应该写$ total_income_query而不是$ stmt。代码应如下所示......

$total_income_query = $db->prepare("select sum(credit) from accounts WHERE STR_TO_DATE(date, '%d/%m/%Y') BETWEEN STR_TO_DATE(:startDate, '%d/%m/%Y') AND STR_TO_DATE(:endDate, '%d/%m/%Y')");

$total_income_query->bindParam(':startDate',$startDate);
$total_income_query->bindParam(':endDate',$endDate);
$total_income_query->execute();

$total = $total_income_query->fetch(PDO::FETCH_NUM);

echo $total_income = $total[0];

如何在PDO查询中获取列的SUM

2 个答案: