这个“已付或未付发票”MySQL 查询是否可行？

Question

我正在尝试生成一个显示“已付款”发票的查询。我的查询不起作用，这意味着其中存在错误，或者我试图以这种方式实现的目标是不可能的。

// paid

$statement = "accounts_invoice i 
               INNER JOIN customer_type ct on i.invoice_customer_type = ct.customer_type_id 
               LEFT JOIN accounts_invoice_payment ip on i.invoice_id = ip.invoice_payment_invoice_id 
              WHERE invoice_posted='1' 
                AND (i.invoice_total_amount_exc_vat + i.invoice_total_vat_amount) = ip.TotalPayments" 
              . $where 
              . " ORDER BY invoice_id DESC";

$invoice_details_query = mysqli_query($con,
          "SELECT i.*, ct.customer_type_name, 
                  ip.invoice_payment_amount AS TotalPayments 
           FROM {$statement} 
           LIMIT {$startpoint} , {$per_page}") 
        or die(mysql_error());

在这种情况下$where 字符串为空，您可以根据需要将其删除。您也可以删除“LIMIT”，因为这纯粹是用于分页。

我只是想创建一个页面来显示已付或未付的发票，考虑到这在理论上听起来如此简单，这让我发疯了！

数据库结构；

-- phpMyAdmin SQL Dump
-- version 4.0.10.7
-- http://www.phpmyadmin.net
--
-- Host: localhost
-- Generation Time: Aug 08, 2015 at 05:17 PM
-- Server version: 5.1.73-cll
-- PHP Version: 5.4.31

SET SQL_MODE = "NO_AUTO_VALUE_ON_ZERO";
SET time_zone = "+00:00";

--
-- Database: `propsyst_atlas`
--

-- --------------------------------------------------------

--
-- Table structure for table `accounts_invoice`
--

CREATE TABLE IF NOT EXISTS `accounts_invoice` (
  `invoice_id` int(11) NOT NULL AUTO_INCREMENT,
  `invoice_customer_type` tinyint(4) DEFAULT NULL,
  `invoice_customer` int(11) DEFAULT NULL,
  `invoice_date` date DEFAULT NULL,
  `invoice_due_date` date DEFAULT NULL,
  `invoice_property_id` int(11) DEFAULT NULL,
  `invoice_tenancy_id` int(11) DEFAULT NULL,
  `invoice_branch` int(11) DEFAULT NULL,
  `invoice_payment_terms` tinyint(4) DEFAULT NULL,
  `invoice_notes` text COLLATE utf8_bin,
  `invoice_total_amount_exc_vat` decimal(10,2) DEFAULT NULL,
  `invoice_total_vat_amount` decimal(10,2) DEFAULT NULL,
  `invoice_posted` tinyint(4) DEFAULT '0',
  `invoice_date_created` datetime DEFAULT NULL,
  `invoice_date_updated` datetime DEFAULT NULL,
  `invoice_date_posted` datetime DEFAULT NULL,
  `invoice_created_by` int(11) DEFAULT NULL,
  `invoice_updated_by` int(11) DEFAULT NULL,
  `invoice_posted_by` int(11) DEFAULT NULL,
  PRIMARY KEY (`invoice_id`)
) ENGINE=MyISAM  DEFAULT CHARSET=utf8 COLLATE=utf8_bin AUTO_INCREMENT=87 ;


-- phpMyAdmin SQL Dump
-- version 4.0.10.7
-- http://www.phpmyadmin.net
--
-- Host: localhost
-- Generation Time: Aug 08, 2015 at 05:18 PM
-- Server version: 5.1.73-cll
-- PHP Version: 5.4.31

SET SQL_MODE = "NO_AUTO_VALUE_ON_ZERO";
SET time_zone = "+00:00";

--
-- Database: `propsyst_atlas`
--

-- --------------------------------------------------------

--
-- Table structure for table `accounts_invoice_payment`
--

CREATE TABLE IF NOT EXISTS `accounts_invoice_payment` (
  `invoice_payment_id` int(11) NOT NULL AUTO_INCREMENT,
  `invoice_payment_date` date DEFAULT NULL,
  `invoice_payment_amount` decimal(10,2) DEFAULT NULL,
  `invoice_payment_method` tinyint(4) DEFAULT NULL,
  `invoice_payment_invoice_id` int(11) DEFAULT NULL,
  `invoice_payment_notes` text COLLATE utf8_bin,
  `invoice_payment_date_created` datetime DEFAULT NULL,
  `invoice_payment_date_updated` datetime DEFAULT NULL,
  `invoice_payment_created_by` int(11) DEFAULT NULL,
  `invoice_payment_updated_by` int(11) DEFAULT NULL,
  PRIMARY KEY (`invoice_payment_id`)
) ENGINE=MyISAM  DEFAULT CHARSET=utf8 COLLATE=utf8_bin AUTO_INCREMENT=71 ;

-- phpMyAdmin SQL Dump
-- version 4.0.10.7
-- http://www.phpmyadmin.net
--
-- Host: localhost
-- Generation Time: Aug 08, 2015 at 05:58 PM
-- Server version: 5.1.73-cll
-- PHP Version: 5.4.31

SET SQL_MODE = "NO_AUTO_VALUE_ON_ZERO";
SET time_zone = "+00:00";

--
-- Database: `propsyst_atlas`
--

-- --------------------------------------------------------

--
-- Table structure for table `customer_type`
--

CREATE TABLE IF NOT EXISTS `customer_type` (
  `customer_type_id` int(11) NOT NULL AUTO_INCREMENT,
  `customer_type_name` varchar(20) COLLATE utf8_bin DEFAULT NULL,
  PRIMARY KEY (`customer_type_id`)
) ENGINE=MyISAM  DEFAULT CHARSET=utf8 COLLATE=utf8_bin AUTO_INCREMENT=4 ;

Answer 1

实际上您的查询是

SELECT
    i.*,
    ip.invoice_payment_amount AS TotalPayments
FROM accounts_invoice i 
LEFT JOIN accounts_invoice_payment ip
    ON i.invoice_id = ip.invoice_payment_invoice_id 
WHERE invoice_posted='1' 
AND (i.invoice_total_amount_exc_vat + i.invoice_total_vat_amount) = ip.TotalPayments
ORDER BY invoice_id DESC

并且该查询失败，因为 where 语句中的 ip.TotalPayments 是未知列。您需要使用原始名称ip.invoice_payment_amount。别名只在返回的集合中使用，而不是在查询本身中。

此外，您的数据库设计还可以改进。首先，我建议使用InnoDB 而不是MyISAM。这允许您使用外键，因此表之间实际上存在关系。

另外，我会将WHERE 子句的AND 部分移至ON 子句，如下所示：

SELECT
    i.*,
    ip.invoice_payment_amount AS TotalPayments
FROM accounts_invoice i 
LEFT JOIN accounts_invoice_payment ip
    ON i.invoice_id = ip.invoice_payment_invoice_id 
    AND (i.invoice_total_amount_exc_vat + i.invoice_total_vat_amount) = ip.invoice_payment_amount
WHERE invoice_posted='1' 
ORDER BY invoice_id DESC

SELECT * FROM A LEFT JOIN B ON A.id = B.a_id 的结果包含A 的每一行以及B 的匹配行。如果B 没有与A 中的行匹配的行，则B 中的列的值为NULL。如果您不希望这样，而只想要在B 中具有匹配行的A 行，则应使用INNER JOIN。