在while循环内查询

Question

这段代码是否有问题？

while($qtytoAdd > 0) {
    if(($remBalance - $qtytoAdd) >= 0) {
        mysql_query('UPDATE `estimates` SET `qty_rec` = `qty_rec` + "'.$qtytoAdd.'" WHERE `proj_id` = "'.$proj_id.'" AND `mat_id` = "'.mat_id_from_mat_desc($materials).'" AND `est_id` = "'.$balid.'"');
        mysql_query('UPDATE `requestdetails` SET `current_rec_qty` = `current_rec_qty` + "'.$qtytoAdd.'" WHERE `proj_id` = "'.$proj_id.'" AND `mat_id` = "'.mat_id_from_mat_desc($materials).'" AND `req_id` = "'.$currid.'"');
    } else {
        mysql_query('UPDATE `estimates` SET `qty_rec` = "'.$remBalance.'" + "'.$currRec.'" WHERE `proj_id` = "'.$proj_id.'" AND `mat_id` = "'.mat_id_from_mat_desc($materials).'" AND `est_id` = "'.$balid.'"');
        mysql_query('UPDATE `requestdetails` SET `current_rec_qty` = "'.$remBalance.'" + "'.$currRec.'" WHERE `proj_id` = "'.$proj_id.'" AND `mat_id` = "'.mat_id_from_mat_desc($materials).'" AND `req_id` = "'.$currid.'"');
        $qtytoAdd = $qtytoAdd - $remBalance;
    }
    return $qtytoAdd;
}

这两个条件似乎都正常，但是我将为$qtytoAdd分配新值的$qtytoAdd却不起作用。 我是否需要使用return函数使其继续循环。 我是新手。 请帮忙。

foreach($mat_desc as $mat_key => $materials){
    $qtytoAdd = $rec_qty[$mat_key];
    $remBalance = mysql_result(mysql_query('SELECT `est_qty` - `qty_rec` as balance FROM `estimates` WHERE `proj_id` = "'.$proj_id.'" AND `mat_id` = "'.mat_id_from_mat_desc($materials).'" AND `qty_rec` <> `est_qty` ORDER BY `item_id` ASC'), 0);
    $balid = mysql_result(mysql_query('SELECT `est_id` FROM `estimates` WHERE `proj_id` = "'.$proj_id.'" AND `mat_id` = "'.mat_id_from_mat_desc($materials).'" AND `qty_rec` <> `est_qty` ORDER BY `item_id` ASC'), 0);
    $currRec = mysql_result(mysql_query('SELECT `qty_rec` FROM `estimates` WHERE `proj_id` = "'.$proj_id.'" AND `mat_id` = "'.mat_id_from_mat_desc($materials).'" AND `qty_rec` <> `est_qty`'), 0);
    $currid = mysql_result(mysql_query('SELECT `req_id` FROM `requestdetails` JOIN `request` USING(`req_id`) WHERE `proj_id` = "'.$proj_id.'" AND `mat_id` = "'.mat_id_from_mat_desc($materials).'" AND `req_qty` <> `current_rec_qty` ORDER BY `req_id` ASC'), 0);

    mysql_query('INSERT INTO `receivedetails` (`rec_id`,`mat_id`,`rec_qty`) VALUES ('.$rec_id.','.mat_id_from_mat_desc($materials).','.$qtytoAdd.')');

    while($qtytoAdd > 0) {
        if(($remBalance - $qtytoAdd) >= 0) {
            mysql_query('UPDATE `estimates` SET `qty_rec` = `qty_rec` + "'.$qtytoAdd.'" WHERE `proj_id` = "'.$proj_id.'" AND `mat_id` = "'.mat_id_from_mat_desc($materials).'" AND `est_id` = "'.$balid.'"');
            mysql_query('UPDATE `requestdetails` SET `current_rec_qty` = `current_rec_qty` + "'.$qtytoAdd.'" WHERE `proj_id` = "'.$proj_id.'" AND `mat_id` = "'.mat_id_from_mat_desc($materials).'" AND `req_id` = "'.$currid.'"');
            $qtytoAdd = 0;
        } else {
            mysql_query('UPDATE `estimates` SET `qty_rec` = "'.$remBalance.'" + "'.$currRec.'" WHERE `proj_id` = "'.$proj_id.'" AND `mat_id` = "'.mat_id_from_mat_desc($materials).'" AND `est_id` = "'.$balid.'"');
            mysql_query('UPDATE `requestdetails` SET `current_rec_qty` = "'.$remBalance.'" + "'.$currRec.'" WHERE `proj_id` = "'.$proj_id.'" AND `mat_id` = "'.mat_id_from_mat_desc($materials).'" AND `req_id` = "'.$currid.'"');
            $qtytoAdd = $qtytoAdd - $remBalance;
        }
    }

    mysql_query('UPDATE `estimates` SET `qty_onhand` = `qty_rec` - `qty_rel` WHERE `proj_id` = '.$proj_id.' AND `qty_rec` <> `est_qty` AND `mat_id` = '.mat_id_from_mat_desc($materials).' AND `est_id` = '.$balid.'');
}

这实际上是整个代码。 ：]

Answer 1

我是否需要使用return函数使其继续循环

您无需返回即可继续循环。 要从当前函数返回并返回时，可以使用return 。

如果从函数内部调用，则return语句将立即结束当前函数的执行，并将其参数作为函数调用的值返回。 return也将结束eval（）语句或脚本文件的执行。

PHP和查询

while($qtytoAdd > 0) {
    if(($remBalance - $qtytoAdd) >= 0) {
        mysql_query('UPDATE `estimates` SET `qty_rec` = `qty_rec` + "'.$qtytoAdd.'" WHERE `proj_id` = "'.$proj_id.'" AND `mat_id` = "'.mat_id_from_mat_desc($materials).'" AND `est_id` = "'.$balid.'"');
        mysql_query('UPDATE `requestdetails` SET `current_rec_qty` = `current_rec_qty` + "'.$qtytoAdd.'" WHERE `proj_id` = "'.$proj_id.'" AND `mat_id` = "'.mat_id_from_mat_desc($materials).'" AND `req_id` = "'.$currid.'"');
        $qtytoAdd = $qtytoAdd - $remBalance; // this part does not exist in your code.
        ^^^^^^^^^^^^^^^^^^^^^^-------- depends on your requirement. I added the same line.  
 } else {
        mysql_query('UPDATE `estimates` SET `qty_rec` = "'.$remBalance.'" + "'.$currRec.'" WHERE `proj_id` = "'.$proj_id.'" AND `mat_id` = "'.mat_id_from_mat_desc($materials).'" AND `est_id` = "'.$balid.'"');
        mysql_query('UPDATE `requestdetails` SET `current_rec_qty` = "'.$remBalance.'" + "'.$currRec.'" WHERE `proj_id` = "'.$proj_id.'" AND `mat_id` = "'.mat_id_from_mat_desc($materials).'" AND `req_id` = "'.$currid.'"');
        $qtytoAdd = $qtytoAdd - $remBalance;
    }
}

你哪里错了

根据您的代码，如果第一个条件为true，则不要对$ qtytoAdd进行更改。 另外，您还可以从函数中返回。 因此，while循环将仅执行一次。