如何将计算字段插入数据库？

Question

我正在向数据库中插入多条记录。 许多字段是一致的，但是计算一个字段，需要为插入数据库的每条记录计算/减去值。

<?php
$ExecuteQuery = new WA_MySQLi_Query($numeroseti);
$ExecuteQuery->Statement = "INSERT INTO transactions 
(fromAcct, amount, fromAcctNewBalance, toAcctNewBalance, toAcct, description, timestamp) 
(SELECT 1, ?, ?, balance + ?, acct_number, 'issuance', $time FROM users WHERE acct_number NOT LIKE '1800%' AND type <> 1 AND user_active = 1)";
$ExecuteQuery->bindParam("d", "".($_POST['issue_balance'])  ."", "0"); //acct1num
$ExecuteQuery->bindParam("i", "".($getSender->getColumnVal("balance") - $amount)  ."", "-1");
//acct2num
$ExecuteQuery->bindParam("i", "".($amount)  ."", "-1");
//acct3num
$ExecuteQuery->execute();
?>

该字段来自我遇到问题的fromAcctNewBalance 。 这是计算（如分类帐）新余额的代码：

$getSender->getColumnVal("balance") - $amount;

问题是，它会将相同的值放入每条记录中，而每次添加新记录时它应该减去该数量。

例如，如果fromAcctNewBalance起始余额为 600，发给用户的金额为 10，则添加的下一条记录的fromAcctNewBalance应为 590，依此类推，直到它用完要添加到表中的记录为止。

有人对我如何解决此问题有任何想法吗？

Answer 1

我认为错误在于在bindParam中使用-> 。

所以我尝试在没有bindParam和$getSender->$getColumnVal - $amount;的情况下进行减法。 根本行不通。

像这样使用它

$getSender = $getColumnVal("balance") - $amount;
$ExecuteQuery->bindParam("i", "".($getSender)  ."", "-1");

" -> ，当您想要调用实例上的方法或访问实例属性时使用。"

我不清楚您的$getColumnVal("balance")是方法还是实例。 如果是这样，请像这样使用它：

$getSender -> $getColumnVal("balance");
$getSender = $getSender - $amount;
$ExecuteQuery->bindParam("i", "".($getSender)  ."", "-1");

参考：

我们在哪里使用 PHP 中的 object 运算符“->”？

https://www.php.net/manual/de/language.types.object.php

编辑：

完整代码示例

<?php
$ExecuteQuery = new WA_MySQLi_Query($numeroseti);
$ExecuteQuery->Statement = "INSERT INTO transactions 
(fromAcct, amount, fromAcctNewBalance, toAcctNewBalance, toAcct, description, timestamp) 
(SELECT 1, ?, ?, balance + ?, acct_number, 'issuance', $time FROM users WHERE acct_number NOT LIKE '1800%' AND type <> 1 AND user_active = 1)";
$ExecuteQuery->bindParam("d", "".($_POST['issue_balance'])  ."", "0"); //acct1num

//Use the one that fits best
    $getSender = $getColumnVal("balance") - $amount;
    $ExecuteQuery->bindParam("i", "".($getSender)  ."", "-1");

//or 
    $getSender -> $getColumnVal("balance");
    $getSender = $getSender - $amount;
    $ExecuteQuery->bindParam("i", "".($getSender)  ."", "-1");

//acct2num
$ExecuteQuery->bindParam("i", "".($amount)  ."", "-1");
//acct3num
$ExecuteQuery->execute();
?>

Answer 2

这最终为我工作：

    while (!$getRecipients->atEnd())
{
    $ExecuteQuery = new WA_MySQLi_Query($numeroseti);
    $ExecuteQuery->Statement = "INSERT INTO transactions 
     (fromAcct, amount, fromAcctNewBalance, toAcctNewBalance, toAcct, description, timestamp) 
    VALUES (1, ?, ?, ?, ?, 'issuance', $time)";                 
    $ExecuteQuery->bindParam("i", "".($amount)  ."", "0");
    $ExecuteQuery->bindParam("i", "".($startingbalance)   ."", "-1");   
    $ExecuteQuery->bindParam("i", "".($amount)  ."", "-1");
    $ExecuteQuery->bindParam("i", "".($getRecipients->getColumnVal("acct_number"))  ."", "-1");
    $ExecuteQuery->execute();
    
    $startingbalance = $startingbalance - $amount;
    $getRecipients->moveNext();
}
$getRecipients->moveFirst();