Question

如何从两个表中获取日期报告？

信用表：

------------------------
Date        |   Amount
------------------------
20/10/2014  |    1200
------------------------
10/10/2014  |    3200
------------------------
05/10/2014  |    1300
------------------------

借记卡表：

------------------------
Date        |   Amount
------------------------
20/10/2014  |    2200
------------------------
15/10/2014  |    5200
------------------------
02/10/2014  |    1800
------------------------

输出应为：

Date          Cr           Dr
------------------------------
20/10/2014   1200        2200
15/10/2014      0        5200
10/10/2014   3200           0
05/10/2014   1300           0
02/10/2014      0        1800

我尝试了以下方法：

$date[] = { '20/10/2014','19/10/2014',........Last date };
$i=0;
while ($<sizeof($date)) 
  {
    $credit  = mysql_fetch_assoc(mysql_query("select * from credit where date='".$date[$i]."'"));
    $debit  = mysql_fetch_assoc(mysql_query("select * from debit where date='".$date[$i]."'"));

    echo $credit["amount"]. $debit["amount"];
   }

我在date和from日期之间的所有日期都收集了to。

我知道这是一个糟糕的方法，它减慢了页面的执行速度，所以我怎么能以更聪明的方式解决这个问题？

提前谢谢。

Answer 1

查询

SELECT * FROM (SELECT a.`Date`,
IFNULL(a.Amount, 0) AS Cr,
IFNULL(b.Amount, 0) AS Dr
FROM Credit a 
LEFT JOIN Debit b
ON a.`Date` = b.`Date`
UNION
SELECT b.`date`, 
IFNULL(a.Amount, 0) AS Cr, 
IFNULL(b.Amount, 0) AS Dr
FROM Credit a
RIGHT JOIN Debit b
ON a.`date` = b.`date`)t
ORDER BY t.`Date` DESC;

Demo

Answer 2

使用以下查询，因为mysql中没有外连接使用左右连接

SELECT date, IFNULL(c.amount, 0) AS credit, IFNULL(d.amount, 0) AS debit
FROM credit c LEFT JOIN debit d
ON c.date = d.date
ORDER BY date DESC
UNION
SELECT date, IFNULL(c.amount, 0) AS credit, IFNULL(d.amount, 0) AS debit
FROM credit c RIGHT JOIN debit d
ON c.date = d.date
ORDER BY date DESC

PHP代码就像这样

$query =  'SELECT date, IFNULL(c.amount, 0) AS credit, IFNULL(d.amount, 0) AS credit
           FROM credit c LEFT JOIN debit d
           ON c.date = d.date
           ORDER BY date DESC
           UNION
           SELECT date, IFNULL(c.amount, 0) AS credit, IFNULL(d.amount, 0) AS credit
           FROM credit c RIGHT JOIN debit d
           ON c.date = d.date
           ORDER BY date DESC';

$con = mysqli_connect( ) //Connection string;   

$result = mysqli_query($con,$query);
while($row = mysqli_fetch_array($result))  
    {echo '<tr>
    <td>'.$row["date"].'</td>
    <td>'.$row["credit"].'</td>
    <td>'.$row["debit"].'</td>
    </tr>';

    }

Answer 3

我会使用以下查询，在两个表之间使用左外连接并联内部连接，不包括内部连接匹配记录，并将左表值默认为0.如果信用卡中没有重复日期。借记表可以从sql语句中删除sum方法。

select c.date_, ifnull(sum(c.amount),0)  cr, ifnull(sum(d.amount),0) db from credit c left outer join debit d on c.date_ = d.date_
group by c.date_
union all
select d.date_, 0 cr, ifnull(sum(d.amount),0) db from credit c right outer join debit d on c.date_ = d.date_ where c.date_ is null
group by d.date_
order by date_ desc

在这里，您可以使用sql fiddle链接作为参考

如何按日期对两个mysql表进行分组

3 个答案:

查询

Demo