计算 FPDF 中的利润总和

Question

我有一个包含profit 列的报告。我需要添加利润列的所有值并获得当天的总利润。感谢任何帮助，因为我已经完成了 SO，但没有找到解决方案。

$result = mysqli_query($connection, "SELECT S.sales_id, I.item_name, ST.stock_code, 
  S.date, S.unit_price, SUM(S.qty), (SUM(S.qty)*S.unit_price), 
  ((SUM(S.qty)*S.unit_price)-(SUM(S.qty)*P.unit_cost)) FROM sales S 
  INNER JOIN items I ON S.item_id=I.item_id 
  INNER JOIN stock ST ON S.stock_id=ST.stock_id 
  INNER JOIN purchase_items P ON S.purchase_id=P.purchase_id 
  WHERE S.date BETWEEN '$date 00:00:00' AND '$date 23:59:59' GROUP BY S.item_id");

$qty = $row['SUM(S.qty)'];
$unit_price = $row['unit_price'];
$amount = $row['(SUM(S.qty)*S.unit_price)'];    
$profit = $row['((SUM(S.qty)*S.unit_price)-(SUM(S.qty)*P.unit_cost))']; 
$dailyProfit = $row['(SUM(SUM(S.qty)*S.unit_price)-(SUM(S.qty)*P.unit_cost)))'];
$pdf->Cell(25,10,$dailyProfit,'B',0,'J',1);

这仅检索一条记录，最后一项为profit，应如何更正以获得每日sum(profit)？

更新代码

$result = mysqli_query($connection, "SELECT S.sales_id, I.item_name, ST.stock_code, S.date,
  S.unit_price, SUM(S.qty) AS line_qty, (SUM(S.qty)*S.unit_price) AS line_total, 
  ((SUM(S.qty)*S.unit_price)-(SUM(S.qty)*P.unit_cost)) AS line_profit
  FROM sales S 
  INNER JOIN items I ON S.item_id=I.item_id 
  INNER JOIN stock ST ON S.stock_id=ST.stock_id 
  INNER JOIN purchase_items P ON S.purchase_id=P.purchase_id 
  WHERE S.date BETWEEN '$date 00:00:00' AND '$date 23:59:59' GROUP BY S.item_id");

$qty = $row['line_qty'];
$unit_price = $row['unit_price'];
$amount = $row['line_total'];    
$profit = $row['line_profit']; 

$aRows = array();
while ($oRow = mysqli_fetch_assoc($result)) $aRows[] = $oRow;
mysqli_free_result($result);

$dTotalProfit = 0;
if (count($aRows) > 0) foreach ($aRows as $aRow) {
  $dTotalProfit += $aRow['line_profit'];
  //$pdf->Cell(25, 10, $aRow['line_qty'], 'B', 0, 'J', 1);
}
$totalProfit = number_format($dTotalProfit, 2);

$pdf->Cell(220, 10, 'Daily Total Profit:', 'B', 0, 'R', 1);
$pdf->Cell(25, 10, $totalProfit, 'B', 0, 'J', 1);

Answer 1

您不能将 SQL 函数和表达式应用于 PHP 变量，它们仅在作为 SQL 查询执行时才有效。为了帮助减少混淆并使您的代码尽可能易读，我建议您为计算值分配列名或别名，例如：

<?php
$sSQL = "SELECT S.sales_id, I.item_name, ST.stock_code, S.date, S.unit_price, 
  SUM(S.qty) AS line_qty, (SUM(S.qty)*S.unit_price) AS line_total, 
  ((SUM(S.qty)*S.unit_price)-(SUM(S.qty)*P.unit_cost)) AS line_profit
  FROM sales S 
  INNER JOIN items I ON S.item_id=I.item_id 
  INNER JOIN stock ST ON S.stock_id=ST.stock_id 
  INNER JOIN purchase_items P ON S.purchase_id=P.purchase_id 
  WHERE S.date BETWEEN '$date 00:00:00' AND '$date 23:59:59' GROUP BY S.item_id";

然后您可以使用以下方法访问这些值：

$qty = $row['line_qty'];
$unit_price = $row['unit_price'];
$amount = $row['line_total'];    
$profit = $row['line_profit']; 

要获得每日总利润，您需要将所有返回行的值相加，在这种情况下，这很容易在循环中完成：

$oConnection = mysqli_connect($sHostname, $sUsername, $sPassword);
mysqli_select_db($oConnection, $sDatabaseName);
$oResult = mysqli_query($oConnection, $sSQL);
$aRows = array();
while ($oRow = mysqli_fetch_assoc($oResult)) $aRows[] = $oRow;
mysqli_free_result($result);

$dTotalProfit = 0;
if (count($aRows) > 0) foreach ($aRows as $aRow) {
  $dTotalProfit += $aRow['line_profit'];
  $pdf->Cell(25, 10, $aRow['line_qty'], 'B', 0, 'J', 1);
  ...
}

然后在 PDF 的底部，您可以使用number_format($dTotalProfit, 2) 输出您的每日总利润金额。

---

总结并应用上述所有技术：

$oQuery = mysqli_query($connection, "SELECT S.sales_id, I.item_name, ST.stock_code, S.date,
  S.unit_price, SUM(S.qty) AS line_qty, (SUM(S.qty)*S.unit_price) AS line_total, 
  ((SUM(S.qty)*S.unit_price)-(SUM(S.qty)*P.unit_cost)) AS line_profit
  FROM sales S 
  INNER JOIN items I ON S.item_id=I.item_id 
  INNER JOIN stock ST ON S.stock_id=ST.stock_id 
  INNER JOIN purchase_items P ON S.purchase_id=P.purchase_id 
  WHERE S.date BETWEEN '$date 00:00:00' AND '$date 23:59:59' GROUP BY S.item_id");

$aRows = array();
while ($oRow = mysqli_fetch_assoc($oQuery)) $aRows[] = $oRow;
mysqli_free_result($oQuery);

$aColumnWidths = array(25, 20, 20, 100, 20, 20, 20, 20);
$dTotalProfit = 0;
if (count($aRows) > 0) foreach ($aRows as $aRow) {
  $dTotalProfit += $aRow['line_profit'];
  $pdf->Cell($aColumnWidths[0], 10, $aRow['date'], 'B', 0, 'J', 1);
  $pdf->Cell($aColumnWidths[1], 10, $aRow['sales_id'], 'B', 0, 'J', 1);
  $pdf->Cell($aColumnWidths[2], 10, $aRow['stock_code'], 'B', 0, 'J', 1);
  $pdf->Cell($aColumnWidths[3], 10, $aRow['item_name'], 'B', 0, 'L', 1);
  $pdf->Cell($aColumnWidths[4], 10, $aRow['line_qty'], 'B', 0, 'R', 1);
  $pdf->Cell($aColumnWidths[5], 10, $aRow['unit_price'], 'B', 0, 'R', 1);
  $pdf->Cell($aColumnWidths[6], 10, $aRow['line_total'], 'B', 0, 'R', 1);
  $pdf->Cell($aColumnWidths[7], 10, $aRow['line_profit'], 'B', 0, 'R', 1);
  $pdf->Ln();
}
$pdf->Ln();
$pdf->Cell($aColumnWidths[0] + $aColumnWidths[1] + $aColumnWidths[2] + $aColumnWidths[3] +
  $aColumnWidths[4] + $aColumnWidths[5] + $aColumnWidths[6], 10, 
  'Daily Total Profit:', 'B', 0, 'R', 1);
$pdf->Cell($aColumnWidths[7], 10, number_format($dTotalProfit, 2), 'B', 0, 'R', 1);

在此代码中，您还会注意到我已将日期列移到开头，因为通常在财务报告中，日期将显示在左侧，然后最右侧的利润列将直接在下方显示总计。我猜测您的 $pdf->Cell 行的格式，因为您包含的源代码在包含这些时并不完整。

另外，如果您不熟悉前缀，我在答案源代码中使用了匈牙利表示法，即 $oQuery 中的 o 代表对象，$aRows 中的 a 代表数组，$dTotalProfit 中的 d用于双精度，如果需要，我可能会使用 i 表示整数，b 表示布尔值等。如果您可以从名称中识别变量类型，这只会有助于代码的可读性。