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Php .$row->manufacturerid.“”； 回声“”； }

php mysql

Php .$row->manufacturerid.“”； 回声“”； },php,mysql,pdo,mysqli,Php,Mysql,Pdo,Mysqli,好吧，对于初学者来说，PDO与大型数据库的速度优化毫无关系。 为了更清楚一点，假设你问了一个类似于“如何驾驶我的福特Escort从纽约州布鲁克林到佛罗里达州坦帕”的问题。在这里，汽车制造与此无关。DB驱动程序也是如此 现在转到您的数据库。 你有很多工作要做 首先，绝对不能使用Mysql全文进行分类。它应该只是一个数字索引，链接到具有类别结构的表 因此，查询变得像这样 SELECT * FROM catalog WHERE category=1 AND special = 'YES' AND in

好吧，对于初学者来说，PDO与大型数据库的速度优化毫无关系。
为了更清楚一点，假设你问了一个类似于“如何驾驶我的福特Escort从纽约州布鲁克林到佛罗里达州坦帕”的问题。在这里，汽车制造与此无关。DB驱动程序也是如此

现在转到您的数据库。
你有很多工作要做

首先，绝对不能使用Mysql全文进行分类。它应该只是一个数字索引，链接到具有类别结构的表

因此，查询变得像这样

SELECT * FROM catalog WHERE category=1 AND special = 'YES' AND instock = 'YES' 
AND standardshippingcost=0 ORDER BY lastupdated DESC limit 3;
而且，如果索引正确，它可以非常快。比如说，如果特价商品的数量非常有限，那么无论数据库中有多少条记录，这个字段上的索引都会使它变得很快

但是，整个数据库体系结构可能会有所不同。还有其他的优化方法。但我们不知道你的项目有多少是确定的，老实说，这不是简单的问答形式的问题

编写一个名为
saveCacheData.php
的php脚本，该脚本执行该组sql查询，并将数据转储到名为
cacheData.php
的文件中

在主页上，将sql查询替换为
require\u once（'cacheData.php'）

现在，当mysql表
目录中的数据更新时，请确保也执行
file\u get\u contents（'saveCacheData.php'）
（或者执行某种cron作业，为您缓存数据）


顺便说一句，我确实认为您的DB设计可能会更好，但将DB数据缓存到磁盘通常也是一个好主意。
有一些问题，您可能不会喜欢我所说的

按text/varchar排序的速度非常慢，更新将花费很长时间。您应该做的是将所有文本转换为整数。因此，
广告商类别
中不应包含实际文本。相反，它应该是一个固定长度的
INT
，链接到存储实际文本的表。
special
和
instock
也是如此
standardshippingcost
看起来像一个varchar，因为它在单引号中，如果它是它看起来的样子，那么实际上不应该是这样。如果是数字，则应为数字。我不太确定您的模式，因此，
standardshippingcost
可能需要位于FK链接到
catalog
的自己的表中
lastupdated
在unix时间应为
INT

您的数据应该是
INT
的原因是1）它比
笔记本电脑占用更少的空间（因此排序时的内存更少）-其他
和2）更新速度更快（我假设您使用的是InnoDB）

因此，排序时，
选择所有
id
s（应该是一个自动递增的
PRIMARY
）、
广告商类别
、
instock
、
standardshippingcost
、
standardshippingcost
和
lastupdated
，并将其放入PHP数组中。找到最有效的方式得到你想要的（你会找到捷径）。最后，
按
PRIMARY
键选择特定数据

我会倒回去解释。这种方法将产生最高性能的原因是，如果在没有任何其他索引的InnoDB表上
选择
关闭
主
，不管表有多大，它都会“立即”返回。正如您所经历的那样，使用大型、深奥的查询速度很慢。这就是实际检索数据的方式

PHP在逻辑方面比MySQL快。这就是它的目的。堆栈上有许多Qs显示了这一点。这就是为什么要在PHP上排序。另外，如果您在数据中看到某种统计或其他类型的模式，您实际上可以编写更好的算法，使排序运行得更快

除了unix日期之外，您的其他列不应该太长
Advertiser类别可能会变得有点大，但与
notebook pc-other
相比，它不会是任何东西，后者的长度已经是
19
。我在你的Q中看到大约30个
广告商类别
s，所以这只是一个
INT
长度
2
，因为这是100个潜在值。这将在排序时节省空间和内存

此外，在更新时使用固定长度的整数将更快，因为集群表将始终保持紧凑和碎片整理。如果您的代码>更新< /COD>一个集群中的UnIDB中的一行，从代码>内存（USB闪存驱动器）'<代码> >代码> >投影机'/COD>，您只需使您的数据库对整个数据库进行碎片整理，以删除刚才所做的间隙。如果在固定长度的int列中从一个
1
更改为
10
，则不会执行此操作，因为两者占用相同的空间量，不会产生间隙，因此不需要对集群进行碎片整理

当您这样做时，您会对性能的大幅提高感到震惊，但是是的，这将涉及更多的代码。那么您的优先级是什么，性能还是开发时间




哇！忘记了时间的解释。您想使用它是因为您可以将它存储在
INT
中几秒钟，存储在
DECIMAL
中几微秒。这样做可以在PHP中实现最简单的操作，因为PHP在unix中。
是的，我主要是一个前端开发人员。开始进入后端。我正在接收xml巨大的xml文件，所以我只是在数据库中创建字段并解析它们。我需要创建多个表，为数据编制索引会有所帮助。你能给我举个例子吗？thks

#fetch data
require_once('db_config.php');
$STH = $DBH->query("
SELECT name, buyurl, imageurl, price, manufacturer, manufacturerid FROM catalog WHERE MATCH advertisercategory AGAINST ('notebook pc - other') AND special = 'YES' AND instock = 'YES' AND standardshippingcost LIKE '0' ORDER BY lastupdated DESC limit 3;
SELECT name, buyurl, imageurl, price, manufacturer, manufacturerid FROM catalog WHERE MATCH advertisercategory AGAINST ('Desktop PC') AND special = 'YES' AND instock = 'YES' AND standardshippingcost LIKE '0' ORDER BY lastupdated DESC limit 3;
SELECT name, buyurl, imageurl, price, manufacturer, manufacturerid FROM catalog WHERE MATCH advertisercategory AGAINST ('Hard Drives - External') AND special = 'YES' AND instock = 'YES' AND standardshippingcost LIKE '0' ORDER BY lastupdated DESC limit 3;
SELECT name, buyurl, imageurl, price, manufacturer, manufacturerid FROM catalog WHERE MATCH advertisercategory AGAINST ('Camcorders - Analog/Digital') AND special = 'YES' AND instock = 'YES' AND standardshippingcost LIKE '0' ORDER BY lastupdated DESC limit 3;
SELECT name, buyurl, imageurl, price, manufacturer, manufacturerid FROM catalog WHERE MATCH advertisercategory AGAINST ('Monitors - LCD Flat Panel') AND special = 'YES' AND instock = 'YES' AND standardshippingcost LIKE '0' ORDER BY lastupdated DESC limit 3;
SELECT name, buyurl, imageurl, price, manufacturer, manufacturerid FROM catalog WHERE MATCH advertisercategory AGAINST ('Software - PC Games') AND special = 'YES' AND instock = 'YES' AND standardshippingcost LIKE '0' ORDER BY lastupdated DESC limit 3;
SELECT name, buyurl, imageurl, price, manufacturer, manufacturerid FROM catalog WHERE MATCH advertisercategory AGAINST ('third party accessories') AND special = 'YES' AND instock = 'YES' AND standardshippingcost LIKE '0' ORDER BY lastupdated DESC limit 3;
SELECT name, buyurl, imageurl, price, manufacturer, manufacturerid FROM catalog WHERE advertisercategory LIKE ('LED TV') AND special = 'YES' AND instock = 'YES' AND standardshippingcost LIKE '0' ORDER BY lastupdated DESC limit 3;
SELECT name, buyurl, imageurl, price, manufacturer, manufacturerid FROM catalog WHERE MATCH advertisercategory AGAINST ('Motherboards - %') AND special = 'YES' AND instock = 'YES' AND standardshippingcost LIKE '0' ORDER BY lastupdated DESC limit 9;
SELECT name, buyurl, imageurl, price, manufacturer, manufacturerid FROM catalog WHERE advertisercategory LIKE ('LED TV') AND special = 'YES' AND instock = 'YES' AND standardshippingcost LIKE '0' ORDER BY lastupdated DESC limit 9;
SELECT name, buyurl, imageurl, price, manufacturer, manufacturerid FROM catalog WHERE MATCH advertisercategory AGAINST ('Hard Drives - External') AND special = 'YES' AND instock = 'YES' AND standardshippingcost LIKE '0' ORDER BY lastupdated DESC limit 9;
SELECT name, buyurl, imageurl, price, manufacturer, manufacturerid FROM catalog WHERE MATCH advertisercategory AGAINST ('CPU Cooling') AND special = 'YES' AND instock = 'YES' AND standardshippingcost LIKE '0' ORDER BY lastupdated DESC limit 9;
SELECT name, buyurl, imageurl, price, manufacturer, manufacturerid FROM catalog WHERE MATCH advertisercategory AGAINST ('CPU Thermal Paste / Grease') AND special = 'YES' AND instock = 'YES' AND standardshippingcost LIKE '0' ORDER BY lastupdated DESC limit 9;
SELECT name, buyurl, imageurl, price, manufacturer, manufacturerid FROM catalog WHERE MATCH advertisercategory AGAINST ('Keyboards') AND special = 'YES' AND instock = 'YES' AND standardshippingcost LIKE '0' ORDER BY lastupdated DESC limit 9;
SELECT name, buyurl, imageurl, price, manufacturer, manufacturerid FROM catalog WHERE MATCH advertisercategory AGAINST ('Memory (USB Flash Drive)') AND special = 'YES' AND instock = 'YES' AND standardshippingcost LIKE '0' ORDER BY lastupdated DESC limit 9;
SELECT name, buyurl, imageurl, price, manufacturer, manufacturerid FROM catalog WHERE MATCH advertisercategory AGAINST ('Memory (Desktop Memory)') AND special = 'YES' AND instock = 'YES' AND standardshippingcost LIKE '0' ORDER BY lastupdated DESC limit 9;
SELECT name, buyurl, imageurl, price, manufacturer, manufacturerid FROM catalog WHERE MATCH advertisercategory AGAINST ('Memory (Notebook Memory)') AND special = 'YES' AND instock = 'YES' AND standardshippingcost LIKE '0' ORDER BY lastupdated DESC limit 9;
SELECT name, buyurl, imageurl, price, manufacturer, manufacturerid FROM catalog WHERE MATCH advertisercategory AGAINST ('Mouse') AND special = 'YES' AND instock = 'YES' AND standardshippingcost LIKE '0' ORDER BY lastupdated DESC limit 9;
SELECT name, buyurl, imageurl, price, manufacturer, manufacturerid FROM catalog WHERE MATCH advertisercategory AGAINST ('Printer - Inkjet Printers') AND special = 'YES' AND instock = 'YES' AND standardshippingcost LIKE '0' ORDER BY lastupdated DESC limit 9;
SELECT name, buyurl, imageurl, price, manufacturer, manufacturerid FROM catalog WHERE MATCH advertisercategory AGAINST ('Projectors') AND special = 'YES' AND instock = 'YES' AND standardshippingcost LIKE '0' ORDER BY lastupdated DESC limit 9;
SELECT name, buyurl, imageurl, price, manufacturer, manufacturerid FROM catalog WHERE MATCH advertisercategory AGAINST ('Processors - Desktops') AND special = 'YES' AND instock = 'YES' AND standardshippingcost LIKE '0' ORDER BY lastupdated DESC limit 9;

");

$STH->setFetchMode(PDO::FETCH_OBJ);

while ($row = $STH->fetch()) {
echo "<ul>";
echo "<li>" .$row->name ."</li>";
echo "<li>" .$row->buyurl ."</li>";
echo "<li>" .$row->imageurl ."</li>";
echo "<li>" .$row->price ."</li>";
echo "<li>" .$row->manufacturer ."</li>";
echo "<li>" .$row->manufacturerid ."</li>";
echo "</ul>";
}



SELECT * FROM catalog WHERE category=1 AND special = 'YES' AND instock = 'YES' 
AND standardshippingcost=0 ORDER BY lastupdated DESC limit 3;