查询之间的MySQL数据库查询

这是我的SQL文件：

-- phpMyAdmin SQL Dump
-- version 3.4.7.1
-- http://www.phpmyadmin.net
--
-- Host: localhost
-- Generation Time: Jan 23, 2012 at 09:26 AM
-- Server version: 5.1.56
-- PHP Version: 5.2.9

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


/*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT */;
/*!40101 SET @OLD_CHARACTER_SET_RESULTS=@@CHARACTER_SET_RESULTS */;
/*!40101 SET @OLD_COLLATION_CONNECTION=@@COLLATION_CONNECTION */;
/*!40101 SET NAMES utf8 */;

--
-- Database: `danielle_youtube`
--

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

--
-- Table structure for table `items`
--

CREATE TABLE IF NOT EXISTS `items` (
  `id` int(11) NOT NULL,
  `name` varchar(65) COLLATE utf8_unicode_ci NOT NULL,
  `cost` float NOT NULL,
  `seller_id` int(11) NOT NULL,
  `bids` int(11) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci;

--
-- Dumping data for table `items`
--

INSERT INTO `items` (`id`, `name`, `cost`, `seller_id`, `bids`) VALUES
(1, 'Brand New iMac Computer', 149.99, 32, 3),
(2, 'used diaper from my sister', 2.04, 1, 0),
(3, 'Fresh apple pie', 14.99, 54, 32),
(4, 'New gym socks', 2.34, 90, 566),
(5, 'Weedwacker only slightly used', 4.56, 84, 2),
(6, 'New ipad stolen from best buy', 399, 32, 23),
(7, 'Book about having babies', 21.34, 44, 21),
(8, 'Woman Jeans', 49.5, 56, 123),
(9, 'traditional carpet', 25.45, 14, 75),
(10, '3 boxes of frogs', 30.49, 68, 145),
(11, '48 boxes of frogs', 74.29, 6, 99),
(12, '7 boxes of frogs', 857.75, 18, 88),
(13, 'laptop', 743.3, 89, 158),
(14, 'thumbelina', 228.05, 15, 49),
(15, 'bed', 127.15, 65, 189),
(16, 'shampoing', 12.8, 6, 105),
(17, 'stove', 37.66, 68, 111),
(18, 'cushion', 7.15, 97, 157),
(19, 'refrigerator', 657.49, 61, 129),
(20, 'gold necklace', 853.07, 10, 101),
(21, 'pan', 33.7, 7, 184),
(22, 'awesome alien computer game', 10.75, 18, 29),
(23, 'baby coat', 89.99, 14, 47),
(24, 'baby seat', 145.78, 2, 199),
(25, 'satchel', 44.71, 15, 66),
(26, 'women perfum', 110.9, 48, 84),
(27, 'conveyor belt', 1120.75, 11, 4),
(28, 'used car', 5700.5, 12, 135),
(29, 'supercomputer', 49.75, 50, 176),
(30, 'mirror', 26.8, 19, 56),
(31, 'piano', 1800.4, 13, 147),
(32, 'quitar', 88.4, 25, 164),
(33, 'trumpet', 255.15, 36, 23),
(34, 'machintosh', 3845, 20, 107),
(35, 'earphone', 10.5, 17, 110),
(36, 'computer', 418, 11, 152),
(37, 'night light', 13.87, 97, 198),
(38, 'pc bag', 50.99, 48, 65),
(39, 'babyfoot', 376.7, 2, 121),
(40, 'hairdryer', 88.9, 12, 177),
(41, 'babyliss', 130.75, 68, 79),
(42, 'door', 150.5, 98, 13),
(43, 'baby soap', 12.7, 4, 198),
(44, 'used phone', 43.75, 9, 69),
(45, 'bath', 757.15, 96, 55),
(46, 'flower', 10.75, 16, 89),
(47, 'battery charger', 48.75, 25, 87),
(48, 'air conditioner', 975, 12, 151),
(49, 'casserole', 115.75, 46, 35),
(50, 'used toilet', 180.7, 64, 11),
(51, 'teashirt', 14.98, 65, 114),
(52, 'moto', 920, 22, 174),
(53, 'saxophone', 220.9, 60, 140),
(54, 'bicycle', 180.55, 97, 35),
(55, 'man perfum', 95, 75, 199),
(56, 'table', 157.25, 91, 48),
(57, 'boat', 4890.5, 17, 177),
(58, 'iphone', 547, 8, 28),
(59, 'body milk', 50.5, 16, 90),
(60, 'new curtain for bedroom', 278.4, 92, 11),
(61, 'diamond ring', 1900, 15, 45),
(62, 'swept', 4.5, 9, 99),
(63, 'women hat', 17.55, 39, 60),
(64, 'washing machine', 680.9, 42, 125),
(65, 'baby bottle', 27.98, 91, 117),
(66, 'women sun glasses', 66.7, 18, 174),
(67, 'person weighs', 65.25, 10, 100),
(68, 'photo frame', 18, 85, 170),
(69, 'key board', 16.7, 90, 101),
(70, 'screen', 250, 81, 188),
(71, 'bucket', 2.5, 1, 19),
(72, 'lipstick', 24.75, 3, 44),
(73, 'wardrobe', 120.75, 9, 71),
(74, 'blue dress size 40', 88.9, 7, 113),
(75, 'newspaper', 1.5, 95, 172),
(76, 'scanner', 350, 14, 62),
(77, 'camera', 550.7, 17, 95),
(78, 'camcorder', 788.99, 25, 127),
(79, 'gun', 420.1, 81, 107),
(80, 'domestic dog', 200, 19, 129),
(81, 'horse', 759.5, 30, 115),
(82, 'truck', 7800.5, 32, 123),
(83, 'soccer ball', 95.49, 54, 155),
(84, 'gold earring', 385, 75, 92),
(85, 'basket', 250.45, 46, 142),
(86, 'bikini', 85.2, 12, 57),
(87, 'red skirt', 15.9, 18, 188),
(88, 'copier machine', 800.7, 50, 160),
(89, 'handbag', 35.9, 8, 108),
(90, 'bath towel', 25.1, 11, 186),
(91, 'coffee machine', 210.89, 15, 170),
(92, 'wedding dress', 690, 26, 48),
(93, 'man sun glasses', 80.7, 19, 174),
(94, 'candle', 7.5, 22, 102),
(95, 'scarf', 11.9, 7, 143),
(96, 'microwave', 150.29, 6, 11),
(97, 'electric oven', 645, 62, 171),
(98, 'play station', 256.75, 12, 188),
(99, 'dvd', 126.84, 14, 113),
(100, 'magazine', 3.5, 8, 152);

/*!40101 SET CHARACTER_SET_CLIENT=@OLD_CHARACTER_SET_CLIENT */;
/*!40101 SET CHARACTER_SET_RESULTS=@OLD_CHARACTER_SET_RESULTS */;
/*!40101 SET COLLATION_CONNECTION=@OLD_COLLATION_CONNECTION */;` 

现在，当我运行此查询时：

SELECT name , MIN(cost) FROM items WHERE name LIKE '% boxes of frogs' AND seller_id IN (
       SELECT seller_id FROM items WHERE name LIKE '% boxes of frogs'
       )

我明白了

但当我使用：

SELECT name , MIN(cost) FROM items WHERE seller_id IN(
    SELECT seller_id FROM items WHERE name LIKE '% boxes of frogs'
    )

我得到这个结果：

name: 3 boxes of frogs
MIN(cost): 10.75   

---

我想知道为什么结果不同？

第一个查询返回一盒青蛙的

项目的名称和最便宜的价格（请参阅外部查询中
名称的条件）

第二个查询返回物品的名称和出售一盒青蛙的人出售的任何物品的
items
中的最便宜价格（
name
上的条件仅适用于内部条件）.
因为在外部查询中，您在第二次查询中删除了类似“%boxes of frogs”
的过滤器
名称。@NoDisplayName是的，这就是我想知道该行如何更改结果子查询中的
卖家Id
可以位于多个
名称中
类似
“%boxes of cockroach”
项目中的方式桌子所以您的答案不同，但是从外部查询中删除的外部查询的条件仍然存在于子查询中query@NoDisplayName子查询仍然只返回名称为“%box of frogs”的3个项
name: 3 boxes of frogs
MIN(cost): 10.75