(二)分表思想的引入
近期的文章: 1)高并发数据采集的架构应用(Redis的应用)
2)高可用数据采集平台(如何玩转3门语言php+.net+aauto)
手把手教你做关键词匹配项目这块基本已经完成,深入研究是对系统的性能作为分析,在一些环境的刺激下所必需要做的一些改变。
手把手教你做关键词匹配项目: 手把手教你做关键词匹配项目(搜索引擎)---- 第一天~手把手教你做关键词匹配项目(搜索引擎)---- 第二十二天 (共22篇)
深入研究:上节讲到 关键词匹配项目深入研究-过滤器的引入。
每一篇会分为问题的前因、解决方案以及有些必要的实现方案。
本篇正文正式开始。
问题的前因
随着自动采集数据的爆炸式的增长,词库的容量蒸蒸日上,一下从几W数据猛增几百万数据,小帅帅看着数据库的查询越来越感到无能为力。
再加上小丁丁常对小帅帅说的最多的一句:何时那么选词能快一点,每次我都等好久都莫有反应,真是急死我了。
小帅帅也比较焦急,心力憔悴,真正的感觉到原来这就是挑战。小帅帅无可奈何的继续找到于老大,求于老大赏赐高招。
于老大拍拍小帅帅的肩膀:小伙子,知道项目的难度了吧!
小帅帅回答道:别挖苦我了,我已深深的感受到了,我想我心脏估计快承受不了了。
于老大:就这点你就承受不了,那估计以后有的是给你受的。
小帅帅:大哥,别说这些虚的行不,赶紧的解决方案丫。
于老大:急啥,事情是急不来的,过来,哥给你指条明路。
“每个宝贝是不是有类别的属性,那么这几百万数据真正属于这个类别的词能够有多少?假设我们只取这个类别的词库我们的项目是否可以继续稳定下来”。
解决方案
按照某种业务需要,我们可以对数据表实行分割,可以纵向或者横向分割,可以有效的进行性能优化。
纵向分割也称列分割,把不常用的列或者长字段分割来保证实体处于一个相对适用的状态,常见的有一对一关联。
横向分割也称行分割,按照某种业务拆分数据的记录来存放在不同的表,常见的有按日期分表操作。
本案例是使用横向分割,把数据按照类别的形式进行拆分。
实现方案
我们为了不更改数据表的结构,这样设计了,我们按照表名来区分项目使用那个数据表。这样一来的改动相对是非常少的。我们只需稍微改动下代码就可以解决了,这很心塞的一件事情。
修改Keyword的代码,增加获取数据源。
<?<span>php </span><span>define</span>('DATABASE_HOST','127.0.0.1'<span>); </span><span>define</span>('DATABASE_USER','xiaoshuaishuai'<span>); </span><span>define</span>('DATABASE__PASSWORD','xiaoshuaishuai'<span>); </span><span>define</span>('DATABASE_CHARSET','utf-8'<span>); </span><span>class</span><span> Keyword { </span><span>public</span> <span>$word</span><span>; </span><span>public</span> <span>static</span> <span>$conn</span> = <span>null</span><span>; </span><span>public</span> <span>function</span><span> getDbConn(){ </span><span>if</span>(self::<span>$conn</span> == <span>null</span><span>){ self</span>::<span>$conn</span> = <span>mysql_connect</span>(DATABASE_HOST,DATABASE_USER,<span>DATABASE__PASSWORD); </span><span>mysql_query</span>("SET NAMES '".DATABASE_CHARSET."'",self::<span>$conn</span><span>); </span><span>mysql_select_db</span>("dict",self::<span>$conn</span><span>); </span><span>return</span> self::<span>$conn</span><span>; } </span><span>return</span> self::<span>$conn</span><span>; } </span><span>public</span> <span>function</span><span> save(){ </span><span>$sql</span> = "insert into keywords(word) values ('<span>$this</span>->word')"<span>; </span><span>return</span> <span>mysql_query</span>(<span>$sql</span>,<span>$this</span>-><span>getDbConn()); } </span><span>public</span> <span>static</span> <span>function</span> getWordsSource(<span>$cid</span>,<span>$limit</span>=0,<span>$offset</span>=40<span>){ </span><span>$sql</span> = "SELECT * FROM keywords_<span>$cid</span> LIMIT <span>$limit</span>,<span>$ffset</span>"<span>; </span><span>return</span> DB::MakeArray(<span>$sql</span><span>); } </span><span>public</span> <span>static</span> <span>function</span> getWordsCount(<span>$cid</span><span>){ </span><span>$sql</span> = "SELECT count(*) FROM keywords_<span>$cid</span>"<span>; </span><span>return</span> DB::QueryScalar(<span>$sql</span><span>); } }</span>
DB类新增QueryScalar,用于算总量
<?<span>php </span><span>#</span><span>@author oShine</span> <span>define</span>('DATABASE_HOST','127.0.0.1'<span>); </span><span>define</span>('DATABASE_USER','xiaoshuaishuai'<span>); </span><span>define</span>('DATABASE__PASSWORD','xiaoshuaishuai'<span>); </span><span>define</span>('DATABASE_CHARSET','utf-8'<span>); </span><span>class</span><span> DB { </span><span>public</span> <span>static</span> <span>$conn</span> = <span>null</span><span>; </span><span>public</span> <span>static</span> <span>function</span><span> Connect(){ </span><span>if</span>(self::<span>$conn</span> == <span>null</span><span>){ self</span>::<span>$conn</span> = <span>mysql_connect</span>(DATABASE_HOST,DATABASE_USER,<span>DATABASE__PASSWORD); </span><span>mysql_query</span>("SET NAMES '".DATABASE_CHARSET."'",self::<span>$conn</span><span>); </span><span>mysql_select_db</span>("dict",self::<span>$conn</span><span>); </span><span>return</span> self::<span>$conn</span><span>; } </span><span>return</span> self::<span>$conn</span><span>; } </span><span>public</span> <span>static</span> <span>function</span> Query(<span>$sql</span><span>){ </span><span>return</span> <span>mysql_query</span>(<span>$sql</span>,self::<span>Connect()); } </span><span>public</span> <span>static</span> <span>function</span> makeArray(<span>$sql</span><span>){ </span><span>$rs</span> = self::Query(<span>$sql</span><span>); </span><span>$result</span> = <span>array</span><span>(); </span><span>while</span>(<span>$data</span> = <span>mysql_fetch_assoc</span>(<span>$rs</span><span>)){ </span><span>$result</span>[] = <span>$data</span><span>; } </span><span>return</span> <span>$result</span><span>; } </span><span>public</span> <span>static</span> <span>function</span> QueryScalar(<span>$sql</span><span>){ </span><span>$rs</span> = self::Query(<span>$sql</span><span>); </span><span>$data</span> = <span>mysql_fetch_array</span>(<span>$rs</span><span>); </span><span>if</span>(<span>$data</span> == <span>false</span> || <span>empty</span>(<span>$data</span>) || !<span>isset</span>(<span>$data</span>[1])) <span>return</span> 0<span>; </span><span>return</span> <span>$data</span>[1<span>]; } } </span>
修改Selector的代码,用于选词:
<?<span>php </span><span>#</span><span>@Filename:selector/Selector.php</span><span> #</span><span>@Author:oshine</span> <span>require_once</span> <span>dirname</span>(<span>__FILE__</span>) . '/SelectorItem.php'<span>; </span><span>require_once</span> <span>dirname</span>(<span>__FILE__</span>) . '/charlist/CharList.php'<span>; </span><span>require_once</span> <span>dirname</span>(<span>__FILE__</span>) . '/charlist/CharlistHandle.php'<span>; </span><span>require_once</span> <span>dirname</span>(<span>dirname</span>(<span>__FILE__</span>)) . '/lib/Logger.php'<span>; </span><span>class</span><span> Selector { </span><span>private</span> <span>static</span> <span>$charListHandle</span> = <span>array</span><span>( </span>"黑名单" => "BacklistCharListHandle", "近义词" => "LinklistCharListHandle"<span> ); </span><span>public</span> <span>static</span> <span>function</span> select(<span>$num_iid</span><span>) { </span><span>$selectorItem</span> = SelectorItem::createFromApi(<span>$num_iid</span><span>); Logger</span>::trace(<span>$selectorItem</span>-><span>props_name); </span><span>$charlist</span> = <span>new</span><span> CharList(); </span><span>foreach</span> (self::<span>$charListHandle</span> <span>as</span> <span>$matchKey</span> => <span>$className</span><span>) { </span><span>$handle</span> = self::createCharListHandle(<span>$className</span>, <span>$charlist</span>, <span>$selectorItem</span><span>); </span><span>$handle</span>-><span>exec</span><span>(); } </span><span>$selectWords</span> = <span>array</span><span>(); </span><span>$wordsCount</span> = Keyword::getWordsCount(selectorItem-><span>cid); </span><span>$offset</span> = 40<span>; </span><span>$page</span> = <span>ceil</span>(<span>$wordsCount</span>/<span>$offset</span><span>); </span><span>for</span>(<span>$i</span>=0;<span>$i</span><=<span>$page</span>;<span>$i</span>++<span>){ </span><span>$limit</span> = <span>$i</span>*<span>$offset</span><span>; </span><span>$keywords</span> = Keyword::getWordsSource(selectorItem->cid,<span>$limit</span>,<span>$offset</span><span>); </span><span>foreach</span> (<span>$keywords</span> <span>as</span> <span>$val</span><span>) { </span><span>#</span><span> code...</span> <span>$keywordEntity</span> = SplitterApp::<span>split</span>(<span>$val</span>["word"<span>]); </span><span>#</span><span> code...</span> <span>if</span>(MacthExector::macth(<span>$keywordEntity</span>,<span>$charlist</span><span>)){ </span><span>$selectWords</span>[] = <span>$val</span>["word"<span>]; } } } </span><span>return</span> <span>$selectWords</span><span>; } </span><span>public</span> <span>static</span> <span>function</span> createCharListHandle(<span>$className</span>, <span>$charlist</span>, <span>$selectorItem</span><span>) { </span><span>if</span> (<span>class_exists</span>(<span>$className</span><span>)) { </span><span>return</span> <span>new</span> <span>$className</span>(<span>$charlist</span>, <span>$selectorItem</span><span>); } </span><span>throw</span> <span>new</span> <span>Exception</span>("class not exists", 0<span>); } }</span>
总结
小帅帅又学到了新的知识点,这是要犒劳于老大的节奏吗?你们是否也要犒劳下我呢,求赞哈!