来自不同表中多个记录的一个字段的Php mysql和

Question

我有一个脚本，它从holiday_entitlement表中的当前记录中获取员工的休假权利。

然后，对要从数据库中减去的每个假日请求使用此应享待遇数字。

例如:应享权利天数= 27

假期申请日=2 >>>>应享权利日= 25

假日申请日=4个>>>>应享权利日= 21天

假期申请日=1 >>>>应享权利日剩余的20天，依此类推。

在我的脚本中，剩下的权利天数是$remainder

我正在挣扎的一点是，每当请求被批准或在SQL中计算出原始的应享权利数字减去对该雇员的所有请求、该学年以及如果该请求获得批准时，都能够将该$remainder保存到holiday_entitlement表。

   <?php
    $is_business_result = mysql_query('SELECT * FROM holiday_entitlement WHERE employee = \'' . $username . '\' AND academic_year = \'' . $acyear . '\' ');

    if($is_business = mysql_fetch_array($is_business_result)) {
    echo'<div style="float:left; width:400px;">';

    echo'<table width="100%">
    <tr>
    <td><strong>Name:</strong></td>
    <td>'.$is_business['employee'].'</td>
    </tr>
    <tr>
    <td><strong>Entitlement:</strong></td>
    <td>'.$is_business['new_entitlement'].' '.$is_business['units'].'</td>
    </tr>
    <tr>
    <td><strong>Department / Division:</strong></td>
    <td>'.$is_business['division'].'</td>
    </tr>
    <tr>
    <td><strong>Line Manager:</strong></td>
    <td>'.$is_business['line_manager'].'</td>
    </tr>
    </table>';

    echo'</div>';





    echo'<table class="dataTable" id="business_days_table" cellpadding="2" cellspacing="2" width="100%">
    <thead>
    <th>Start Date</th>
    <th>End Date</th>
    <th>Days to be taken</th>
    <th>Days remaining</th>
    </thead>';

    echo '<tr>';

    echo '<td>-</td>';
    echo '<td>-</td>';
    echo '<td>-</td>';
    echo '<td>'.$is_business['new_entitlement'].'</td>';

    echo '</tr>';


    $input = $is_business['new_entitlement'];
    }

    else {echo 'You currently dont have a record for this academic year. ';}


    $requests_result = mysql_query('SELECT * FROM requests WHERE employee = \'' . $username . '\' AND approved = 1 AND academic_year = \'' . $acyear . '\' ORDER BY start_date ASC');

    $remainder = 0;

    while($requests = mysql_fetch_array($requests_result)) {

    $start_date = new DateTime($requests['start_date']);
    $end_date = new DateTime($requests['end_date']);

    $timestamp_start_date = $start_date->getTimestamp();
    $timestamp_end_date = $end_date->getTimestamp();

    $formatted_start_date = date("d M Y", $timestamp_start_date);           
    $formatted_end_date = date("d M Y", $timestamp_end_date);   

    $remainder = ($remainder == 0) ? $input : $remainder;
    $out = $remainder - $requests['days'];
    if($out < 0){
          break;
    }
    $remainder = $out;


    echo'<tr>';
    echo'<td>'.$formatted_start_date.'</td>';
    echo'<td>'.$formatted_end_date.'</td>';
    echo'<td>'.$requests['days'].'</td>';
    echo'<td>'.$remainder.'</td>';
    echo'</tr>';
    }

    echo'</table>';

    ?>

Answer 1

在SQL中计算出原始的应享权利数字减去对该雇员的所有请求、该学年以及是否获得批准。

应该是这样：

select new_entitlement-(select sum(days) from requests where employee="sashn" and academic_year=2012 and approved=1) from holiday_entitlement where employee="sashn";

或更新：

update holiday_entitlement set new_entitlement=27-(select sum(days) from requests where employee="sashn" and academic_year=2012 and approved=1) where employee="sashn" and academic_year=2012;