我有两张桌子：
hair_product_table 22 products
mix_product_tables 300 products table
示例数据：
select version() as 'mysql version';
DROP TABLE IF EXISTS `hair_product_table`;
CREATE TABLE IF NOT EXISTS `hair_product_table` (
`idphair` smallint(5) UNSIGNED NOT NULL AUTO_INCREMENT,
`productname` varchar(60) NOT NULL,
`description` text,
`pic` text,
PRIMARY KEY (`idphair`)
) ENGINE=InnoDB AUTO_INCREMENT=27 DEFAULT CHARSET=utf8;
DROP TABLE IF EXISTS `mix_product_tables`;
CREATE TABLE IF NOT EXISTS `mix_product_tables` (
`idmix` smallint(5) UNSIGNED NOT NULL AUTO_INCREMENT,
`productname` varchar(256) NOT NULL,
`pic` text,
`description` text,
PRIMARY KEY (`idmix`)
) ENGINE=InnoDB AUTO_INCREMENT=2776 DEFAULT CHARSET=utf8;
#insert dadata for hair_product_table
INSERT INTO `hair_product_table` (`idphair`, `productname`, `description`, `pic`) VALUES
(4, 'jselwe','',''),
(5, 'ddd','',''),
(6, 'jselwe','',''),
(7, 'jelwe','',''),
(8, 'jelwe','',''),
(9, 'jelwe','',''),
(10, 'jelwe','',''),
(11, 'jelwe','',''),
(12, 'jelwe','',''),
(13, 'jelwe','',''),
(14, 'jelwe','',''),
(15, 'jelwe','',''),
(16, 'jelwe','',''),
(17, 'jelwe','',''),
(18, 'jelwe','',''),
(19, 'jelwe','',''),
(20, 'jelwe','',''),
(21, 'jelwe','',''),
(22, 'jelwe','',''),
(23, 'jelwe','',''),
(24, 'jelwe','',''),
(25, 'jelwe','',''),
(26, 'jelwe','',''),
(27, 'jelwe','','');
#insert dadata for mix_product_tables
INSERT INTO `mix_product_tables` (`idmix`, `productname`, `description`, `pic`) VALUES
(1, 'mix1','',''),
(2, 'mix2','',''),
(3, 'mix3','',''),
(4, 'mix4','',''),
(5, 'mix5','',''),
(6, 'jselwe','',''),
(7, 'jelwe','',''),
(8, 'jelwe','',''),
(9, 'jelwe','',''),
(10, 'jelwe','',''),
(11, 'jelwe','',''),
(12, 'jelwe','',''),
(13, 'jelwe','',''),
(14, 'jelwe','',''),
(15, 'jelwe','',''),
(16, 'jelwe','',''),
(17, 'jelwe','',''),
(18, 'jelwe','',''),
(19, 'jelwe','',''),
(20, 'jelwe','',''),
(21, 'jelwe','',''),
(22, 'jelwe','',''),
(23, 'jelwe','',''),
(24, 'jelwe','',''),
(25, 'jelwe','',''),
(26, 'jelwe','',''),
(27, 'jelwe','',''),
(28, 'jselwe','',''),
(29, 'ddd','',''),
(30, 'ddd','',''),
(31, 'jselwe','',''),
(32, 'ddd','',''),
(33, 'jselwe','',''),
(34, 'jelwe','',''),
(35, 'jelwe','',''),
(36, 'jelwe','',''),
(37, 'jelwe','',''),
(38, 'jelwe','',''),
(39, 'jelwe','',''),
(40, 'jelwe','',''),
(41, 'jelwe','',''),
(42, 'jelwe','',''),
(43, 'jelwe','',''),
(44, 'jelwe','',''),
(45, 'jelwe','',''),
(46, 'jelwe','',''),
(47, 'jelwe','',''),
(48, 'jelwe','',''),
(49, 'jelwe','',''),
(50, 'jelwe','',''),
(51, 'jelwe','',''),
(52, 'jelwe','',''),
(53, 'jelwe','',''),
(54, 'jelwe','',''),
(55, 'jselwe','',''),
(56, 'ddd','',''),
(57, 'ddd','',''),
(58, 'jselwe','',''),
(59, 'ddd','',''),
(60, 'jselwe','',''),
(61, 'jelwe','',''),
(62, 'jelwe','',''),
(63, 'jelwe','',''),
(64, 'jelwe','',''),
(65, 'jelwe','',''),
(66, 'jelwe','',''),
(67, 'jelwe','',''),
(68, 'jelwe','',''),
(69, 'jelwe','',''),
(70, 'jelwe','',''),
(71, 'jelwe','',''),
(72, 'jelwe','',''),
(73, 'jelwe','',''),
(74, 'jelwe','',''),
(75, 'jelwe','',''),
(76, 'jelwe','',''),
(77, 'jelwe','',''),
(78, 'jelwe','',''),
(79, 'jelwe','',''),
(80, 'jelwe','',''),
(81, 'jelwe','',''),
(82, 'jselwe','',''),
(83, 'ddd','',''),
(84, 'ddd','',''),
(85, 'jselwe','',''),
(86, 'ddd','',''),
(87, 'jselwe','',''),
(88, 'jelwe','',''),
(89, 'jelwe','',''),
(90, 'jelwe','',''),
(91, 'jelwe','',''),
(92, 'jelwe','',''),
(93, 'jelwe','',''),
(94, 'jelwe','',''),
(95, 'jelwe','',''),
(96, 'jelwe','',''),
(97, 'jelwe','',''),
(98, 'jelwe','',''),
(99, 'jelwe','',''),
(100, 'jelwe','',''),
(101, 'jelwe','',''),
(102, 'jelwe','',''),
(103, 'jelwe','',''),
(104, 'jelwe','',''),
(105, 'jelwe','',''),
(106, 'jelwe','',''),
(107, 'jelwe','',''),
(108, 'jelwe','','');
示例查询：
SELECT hpt.productname, hpt.description, hpt.pic, hpt.idphair
FROM hair_product_table hpt
INNER JOIN mix_product_tables AS mpt
UNION SELECT mpt.productname, mpt.description, mpt.pic, mpt.idmix
FROM mix_product_tables AS mpt limit 30;
+-------------+-------------+------+---------+
| productname | description | pic | idphair |
+-------------+-------------+------+---------+
| jselwe | | | 4 |
| ddd | | | 5 |
| jselwe | | | 6 |
| jelwe | | | 7 |
| jelwe | | | 8 |
| jelwe | | | 9 |
| jelwe | | | 10 |
| jelwe | | | 11 |
| jelwe | | | 12 |
| jelwe | | | 13 |
| jelwe | | | 14 |
| jelwe | | | 15 |
| jelwe | | | 16 |
| jelwe | | | 17 |
| jelwe | | | 18 |
| jelwe | | | 19 |
| jelwe | | | 20 |
| jelwe | | | 21 |
| jelwe | | | 22 |
| jelwe | | | 23 |
| jelwe | | | 24 |
| jelwe | | | 25 |
| jelwe | | | 26 |
| jelwe | | | 27 |
| mix1 | | | 1 |
| mix2 | | | 2 |
| mix3 | | | 3 |
| mix4 | | | 4 |
| mix5 | | | 5 |
| jselwe | | | 28 |
+-------------+-------------+------+---------+
并且rextest相同：http://rextester.com/edit/KTAR73194
为了展示所有产品，我没有问题
$query = mysqli_query($dbc,'SELECT hpt.productname, hpt.description, hpt.pic, hpt.idphair
FROM hair_product_table hpt
INNER JOIN mix_product_tables AS mpt
UNION SELECT mpt.productname, mpt.description, mpt.pic, mpt.idmix
FROM mix_product_tables AS mpt limit 30');
现在我想显示更多产品的链接
我在新页面 ore_product_page.php 。
点击此链接时使用Ajax
<div id="show_more_product<?php echo $last_id_product ?>" title="Load more product">More product</div>访问此页面我发送左侧ID
这就是我有问题，$ last_id_product采取最后一个ID＆＃34; id：8＆＃34;而是最后一个id联盟＆＃34; id：30＆＃34;来自表mix_product_table的最后一个产品
我的问题是如何获得union表的确切id，或者我是否可以为2个表从1到30创建一个类似rowNumber的临时列
由于
答案 0 :(得分：0)
我认为你这个荒谬过度错综复杂的问题的核心可以表达如下：
DROP TABLE IF EXISTS a;
CREATE TABLE a(id SERIAL PRIMARY KEY);
DROP TABLE IF EXISTS b;
CREATE TABLE b(id SERIAL PRIMARY KEY);
INSERT INTO a VALUES (1),(2),(3),(4),(5);
INSERT INTO b VALUES (3),(4),(5),(6),(7);
SELECT * FROM a UNION ALL SELECT * FROM b ORDER BY i;
+----+
| id |
+----+
| 1 |
| 2 |
| 3 |
| 3 |
| 4 |
| 4 |
| 5 |
| 5 |
| 6 |
| 7 |
+----+
所以现在这两张桌子混杂在一起。
这可以很容易地解决如下。
SELECT 'a' source
, id
FROM a
UNION
SELECT 'b'
, id
FROM b
ORDER
BY source
, id;
+--------+----+
| source | id |
+--------+----+
| a | 1 |
| a | 2 |
| a | 3 |
| a | 4 |
| a | 5 |
| b | 3 |
| b | 4 |
| b | 5 |
| b | 6 |
| b | 7 |
+--------+----+