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authormuqiuhan <[email protected]>2025-04-02 08:53:11 +0000
committermuqiuhan <[email protected]>2025-04-02 08:53:11 +0000
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downloadblog-9ab45179bce8087483912833a8913d6a5655ccda.tar.gz
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+ N+1 selects problem 与 Prisma ORM
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+ Apr 2, 2025
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+ <p>N+1 查询问题是指在通过 ORM 查询数据时,执行了<strong>一次</strong>初始查询来获取父对象列表(这 <strong>1</strong> 次查询),然后为列表中的<strong>每一个</strong>父对象都单独执行了一次额外的查询来获取其关联的子对象(这 <strong>N</strong> 次查询)。最终导致总共执行了 <strong>1 + N</strong> 次数据库查询,其中 N 是初始查询返回的父对象的数量。</p>
+<p><strong>举个例子:</strong></p>
+<p>假设有两个数据库模型:<code>User</code>(用户)和 <code>Post</code>(帖子),一个用户可以有多篇帖子(一对多关系)。</p>
+<p>现在,需要获取前 10 个用户以及他们各自的所有帖子。</p>
+<p>一种<strong>有问题</strong>的 ORM 实现(或不当的使用方式)可能会这样执行:</p>
+<ol>
+<li><strong>第一次查询 (The “1”)</strong>: 获取前 10 个用户。<figure class="highlight sql"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">SELECT</span> <span class="operator">*</span> <span class="keyword">FROM</span> <span class="keyword">User</span> LIMIT <span class="number">10</span>;</span><br></pre></td></tr></table></figure></li>
+<li><strong>接下来的 N (&#x3D;10) 次查询 (The “N”)</strong>: 对于上一步获取到的每一个用户,单独执行一次查询来获取该用户的帖子。<figure class="highlight sql"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br></pre></td><td class="code"><pre><span class="line"><span class="comment">-- 用户 1</span></span><br><span class="line"><span class="keyword">SELECT</span> <span class="operator">*</span> <span class="keyword">FROM</span> Post <span class="keyword">WHERE</span> authorId <span class="operator">=</span> <span class="number">1</span>;</span><br><span class="line"><span class="comment">-- 用户 2</span></span><br><span class="line"><span class="keyword">SELECT</span> <span class="operator">*</span> <span class="keyword">FROM</span> Post <span class="keyword">WHERE</span> authorId <span class="operator">=</span> <span class="number">2</span>;</span><br><span class="line"><span class="comment">-- 用户 3</span></span><br><span class="line"><span class="keyword">SELECT</span> <span class="operator">*</span> <span class="keyword">FROM</span> Post <span class="keyword">WHERE</span> authorId <span class="operator">=</span> <span class="number">3</span>;</span><br><span class="line"><span class="comment">-- ... 直到 用户 10</span></span><br><span class="line"><span class="keyword">SELECT</span> <span class="operator">*</span> <span class="keyword">FROM</span> Post <span class="keyword">WHERE</span> authorId <span class="operator">=</span> <span class="number">10</span>;</span><br></pre></td></tr></table></figure></li>
+</ol>
+<p>在这个场景下,总共执行了 1 + 10 &#x3D; <strong>11</strong> 次数据库查询。如果 N 的值很大(比如获取 1000 个用户),就会产生 1001 次查询,这对数据库造成巨大的、不必要的压力,并显著增加应用程序的响应时间。每一次数据库交互都有网络延迟和数据库处理的开销,N+1 次查询会将这些开销放大 N 倍。</p>
+<p>N+1 问题通常源于 ORM 处理关联数据的方式,特别是与“懒加载”(Lazy Loading)相关的策略。懒加载是指只有在显式访问关联属性时,ORM 才会去数据库加载这些数据。虽然这在某些情况下可以避免加载不需要的数据,但如果在循环中访问关联属性,就很容易触发 N+1 问题。</p>
+<p>然而,问题的根源在于<strong>没有有效地预先加载(或批量加载)所需的关联数据</strong>。即使不使用严格意义上的懒加载,如果 ORM 在处理关联查询时不够智能,采用了逐个获取关联对象的策略,同样会产生 N+1 查询。</p>
+<p>在 Prisma 出现之前或在其他 ORM 中,解决 N+1 问题常见的方法包括:</p>
+<ol>
+<li><strong>预先加载(Eager Loading)</strong>: 在执行初始查询时,就明确指示 ORM 同时将关联数据也查询出来。这通常通过 SQL 的 <code>JOIN</code> 操作实现。例如,一次性查询出用户和他们的帖子。虽然这减少了查询次数,但复杂的 <code>JOIN</code> 可能会导致查询本身变得庞大和低效,并可能返回冗余数据。</li>
+<li><strong>批量加载(Batch Loading)</strong>: 先执行初始查询获取父对象列表,然后收集所有父对象的 ID,在第二次查询中使用 <code>WHERE IN (...)</code> 子句一次性加载所有相关的子对象。这种方式通常需要两次查询,但避免了 N 次单独的查询。</li>
+</ol>
+<p>Prisma ORM 在设计上就考虑了 N+1 问题,并提供了一种既方便开发者又高效的解决方案。当使用 Prisma Client 查询数据并需要包含关联模型时,Prisma 会自动优化查询,<strong>避免产生 N+1 查询</strong>,主要通过<strong>关系查询(Relation Queries)</strong>中的 <code>include</code> 选项或嵌套读取(nested reads)来实现这一点:</p>
+<p>假设想获取所有用户及其发布的帖子,使用 Prisma Client,可以这样写:</p>
+<figure class="highlight typescript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">import</span> &#123; <span class="title class_">PrismaClient</span> &#125; <span class="keyword">from</span> <span class="string">&#x27;@prisma/client&#x27;</span></span><br><span class="line"></span><br><span class="line"><span class="keyword">const</span> prisma = <span class="keyword">new</span> <span class="title class_">PrismaClient</span>()</span><br><span class="line"></span><br><span class="line"><span class="keyword">async</span> <span class="keyword">function</span> <span class="title function_">getUsersWithPosts</span>(<span class="params"></span>) &#123;</span><br><span class="line"> <span class="keyword">const</span> usersWithPosts = <span class="keyword">await</span> prisma.<span class="property">user</span>.<span class="title function_">findMany</span>(&#123;</span><br><span class="line"> <span class="attr">include</span>: &#123;</span><br><span class="line"> <span class="attr">posts</span>: <span class="literal">true</span>, <span class="comment">// 指示 Prisma 加载关联的 posts</span></span><br><span class="line"> &#125;,</span><br><span class="line"> &#125;)</span><br><span class="line"> <span class="comment">// usersWithPosts 包含了用户列表,每个用户对象中都有一个 posts 数组</span></span><br><span class="line"> <span class="variable language_">console</span>.<span class="title function_">log</span>(usersWithPosts)</span><br><span class="line">&#125;</span><br><span class="line"></span><br><span class="line"><span class="title function_">getUsersWithPosts</span>()</span><br><span class="line"> .<span class="title function_">catch</span>(<span class="function">(<span class="params">e</span>) =&gt;</span> &#123;</span><br><span class="line"> <span class="keyword">throw</span> e</span><br><span class="line"> &#125;)</span><br><span class="line"> .<span class="title function_">finally</span>(<span class="keyword">async</span> () =&gt; &#123;</span><br><span class="line"> <span class="keyword">await</span> prisma.$disconnect()</span><br><span class="line"> &#125;)</span><br></pre></td></tr></table></figure>
+
+<p>当执行上述查询时,Prisma <strong>不会</strong> 生成 N+1 个 SQL 查询。而是首先会分析请求,并将其转化为数量非常有限的高效 SQL 查询。对于上面这个一对多关系的 <code>include</code> 查询,Prisma 通常会执行以下<strong>两步</strong>(类似于批量加载策略):</p>
+<ol>
+<li><strong>查询父模型</strong>: 获取所有 <code>User</code> 记录。<figure class="highlight sql"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">SELECT</span> &quot;public&quot;.&quot;User&quot;.&quot;id&quot;, &quot;public&quot;.&quot;User&quot;.&quot;name&quot;, <span class="comment">/* ... other user fields */</span> <span class="keyword">FROM</span> &quot;public&quot;.&quot;User&quot; <span class="keyword">WHERE</span> <span class="number">1</span><span class="operator">=</span><span class="number">1</span></span><br></pre></td></tr></table></figure></li>
+<li><strong>查询关联的子模型</strong>: 使用上一步获取到的所有用户 <code>id</code>,通过 <code>WHERE IN (...)</code> 子句一次性查询所有相关的 <code>Post</code> 记录。<figure class="highlight sql"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">SELECT</span> &quot;public&quot;.&quot;Post&quot;.&quot;id&quot;, &quot;public&quot;.&quot;Post&quot;.&quot;title&quot;, &quot;public&quot;.&quot;Post&quot;.&quot;authorId&quot;, <span class="comment">/* ... other post fields */</span> <span class="keyword">FROM</span> &quot;public&quot;.&quot;Post&quot; <span class="keyword">WHERE</span> &quot;public&quot;.&quot;Post&quot;.&quot;authorId&quot; <span class="keyword">IN</span> ($<span class="number">1</span>, $<span class="number">2</span>, $<span class="number">3</span>, ...) <span class="comment">/* 这里的 $1, $2, ... 是第一步查到的用户 ID 列表 */</span></span><br></pre></td></tr></table></figure></li>
+</ol>
+<p>Prisma Client 在内存中将这两次查询的结果高效地组合起来,最终返回嵌套的、符合 TypeScript 类型的数据。</p>
+<h2 id="Refs"><a href="#Refs" class="headerlink" title="Refs."></a>Refs.</h2><ul>
+<li><a target="_blank" rel="noopener" href="https://stackoverflow.com/questions/97197/what-is-the-n1-selects-problem-in-orm-object-relational-mapping">Stack Overflow: What is the N+1 selects problem in ORM?</a></li>
+<li><a target="_blank" rel="noopener" href="https://www.prisma.io/docs/orm/prisma-client/queries/query-optimization-performance#solving-the-n1-problem">Prisma Docs: Solving the N+1 problem</a></li>
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+ <div class="year-title">2025</div>
+
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+ <div class="post-list-item">
+ <div class="post-title">
+ <a href="/2025/04/02/N-1-selects-problem-%E4%B8%8E-Prisma-ORM/">
+
+ N+1 selects problem 与 Prisma ORM
+
+ </a>
+ </div>
+
+ <span class="post-date">Apr 2, 2025</span>
+ </div>
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+ 希望路过的人可以添点柴火让这里暖和点
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+ <div class="search-popup">
+ <div class="search-popup-overlay">
+ </div>
+ <div class="search-popup-window" >
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+ <input autocomplete="off" autocapitalize="off" maxlength="80"
+ placeholder="Search Anything" spellcheck="false"
+ type="search" class="search-input">
+ </div>
+ <div class="search-close-btn">
+ <div class="icon close-btn"></div>
+ </div>
+ </div>
+ <div class="search-result-container">
+ </div>
+ </div>
+</div>
+
+<script>
+ const searchConfig = {
+ path : "/search.xml",
+ top_n_per_article: "1",
+ unescape : "false",
+ trigger: "auto",
+ preload: "false"
+ }
+</script>
+<script src="https://cdn.jsdelivr.net/npm/[email protected]/dist/search.js"></script>
+<script src="/js/search.js"></script>
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+ </body>
+</html>
diff --git a/archives/2025/index.html b/archives/2025/index.html
index 9247cc29..60b3ead2 100644
--- a/archives/2025/index.html
+++ b/archives/2025/index.html
@@ -145,6 +145,24 @@
<div class="post-list-item">
<div class="post-title">
+ <a href="/2025/04/02/N-1-selects-problem-%E4%B8%8E-Prisma-ORM/">
+
+ N+1 selects problem 与 Prisma ORM
+
+ </a>
+ </div>
+
+ <span class="post-date">Apr 2, 2025</span>
+ </div>
+
+
+
+
+
+
+
+ <div class="post-list-item">
+ <div class="post-title">
<a href="/2025/03/31/%E5%9C%A8F-%E4%B8%AD%E5%A4%84%E7%90%86%E5%A4%8D%E6%9D%82%E4%BE%9D%E8%B5%96%E6%B3%A8%E5%85%A5%E7%9A%84%E5%AE%9E%E8%B7%B5%E6%8C%87%E5%8D%97/">
在F#中处理复杂依赖注入的实践指南
@@ -300,24 +318,6 @@
</div>
-
-
-
-
-
- <div class="post-list-item">
- <div class="post-title">
- <a href="/2025/02/24/%E4%BA%8C%E3%80%87%E4%BA%8C%E4%BA%94%E5%B9%B4%E4%BA%8C%E6%9C%88%E4%BA%8C%E5%8D%81%E5%9B%9B%E6%97%A5/">
-
- 二〇二五年二月二十四日
-
- </a>
- </div>
-
- <span class="post-date">Feb 24, 2025</span>
- </div>
-
-
<div id="paginator">
<div class=paginator>
diff --git a/archives/2025/page/2/index.html b/archives/2025/page/2/index.html
index 7a7a1a9d..caae2554 100644
--- a/archives/2025/page/2/index.html
+++ b/archives/2025/page/2/index.html
@@ -145,6 +145,24 @@
<div class="post-list-item">
<div class="post-title">
+ <a href="/2025/02/24/%E4%BA%8C%E3%80%87%E4%BA%8C%E4%BA%94%E5%B9%B4%E4%BA%8C%E6%9C%88%E4%BA%8C%E5%8D%81%E5%9B%9B%E6%97%A5/">
+
+ 二〇二五年二月二十四日
+
+ </a>
+ </div>
+
+ <span class="post-date">Feb 24, 2025</span>
+ </div>
+
+
+
+
+
+
+
+ <div class="post-list-item">
+ <div class="post-title">
<a href="/2025/02/19/Repository-pattern-in-Typescript/">
Repository pattern in Typescript
diff --git a/archives/index.html b/archives/index.html
index 04ec7de6..6fd2042c 100644
--- a/archives/index.html
+++ b/archives/index.html
@@ -145,6 +145,24 @@
<div class="post-list-item">
<div class="post-title">
+ <a href="/2025/04/02/N-1-selects-problem-%E4%B8%8E-Prisma-ORM/">
+
+ N+1 selects problem 与 Prisma ORM
+
+ </a>
+ </div>
+
+ <span class="post-date">Apr 2, 2025</span>
+ </div>
+
+
+
+
+
+
+
+ <div class="post-list-item">
+ <div class="post-title">
<a href="/2025/03/31/%E5%9C%A8F-%E4%B8%AD%E5%A4%84%E7%90%86%E5%A4%8D%E6%9D%82%E4%BE%9D%E8%B5%96%E6%B3%A8%E5%85%A5%E7%9A%84%E5%AE%9E%E8%B7%B5%E6%8C%87%E5%8D%97/">
在F#中处理复杂依赖注入的实践指南
@@ -300,24 +318,6 @@
</div>
-
-
-
-
-
- <div class="post-list-item">
- <div class="post-title">
- <a href="/2025/02/24/%E4%BA%8C%E3%80%87%E4%BA%8C%E4%BA%94%E5%B9%B4%E4%BA%8C%E6%9C%88%E4%BA%8C%E5%8D%81%E5%9B%9B%E6%97%A5/">
-
- 二〇二五年二月二十四日
-
- </a>
- </div>
-
- <span class="post-date">Feb 24, 2025</span>
- </div>
-
-
<div id="paginator">
<div class=paginator>
diff --git a/archives/page/10/index.html b/archives/page/10/index.html
index 298199a0..60ee60ee 100644
--- a/archives/page/10/index.html
+++ b/archives/page/10/index.html
@@ -145,6 +145,24 @@
<div class="post-list-item">
<div class="post-title">
+ <a href="/2023/05/02/Rust-Partial-%E8%AF%AD%E4%B9%89/">
+
+ Rust Partial 语义
+
+ </a>
+ </div>
+
+ <span class="post-date">May 2, 2023</span>
+ </div>
+
+
+
+
+
+
+
+ <div class="post-list-item">
+ <div class="post-title">
<a href="/2023/05/01/Rust-%E8%99%9A%E8%A1%A8%E5%B8%83%E5%B1%80%E8%A7%84%E5%88%99%E4%BB%8B%E7%BB%8D/">
Rust 虚表布局规则介绍
@@ -300,24 +318,6 @@
</div>
-
-
-
-
-
- <div class="post-list-item">
- <div class="post-title">
- <a href="/2023/03/01/%E6%B0%94%E8%83%B8/">
-
- 气胸
-
- </a>
- </div>
-
- <span class="post-date">Mar 1, 2023</span>
- </div>
-
-
<div id="paginator">
<div class=paginator>
diff --git a/archives/page/11/index.html b/archives/page/11/index.html
index 04fbdb79..8a97dced 100644
--- a/archives/page/11/index.html
+++ b/archives/page/11/index.html
@@ -145,6 +145,24 @@
<div class="post-list-item">
<div class="post-title">
+ <a href="/2023/03/01/%E6%B0%94%E8%83%B8/">
+
+ 气胸
+
+ </a>
+ </div>
+
+ <span class="post-date">Mar 1, 2023</span>
+ </div>
+
+
+
+
+
+
+
+ <div class="post-list-item">
+ <div class="post-title">
<a href="/2023/03/01/%E7%BA%AF%E7%89%9B%E5%A5%B6%E5%8F%AF%E4%BB%A5%E5%8A%A0%E7%82%B9%E5%95%A5/">
纯牛奶可以加点啥
@@ -302,24 +320,6 @@
</div>
-
-
-
-
-
- <div class="post-list-item">
- <div class="post-title">
- <a href="/2022/11/03/%E4%BA%8C%E9%9B%B6%E4%BA%8C%E4%BA%8C%E5%B9%B4%E5%8D%81%E4%B8%80%E6%9C%88%E6%9C%88%E4%B8%89%E6%97%A5/">
-
- 二零二二年十一月月三日
-
- </a>
- </div>
-
- <span class="post-date">Nov 3, 2022</span>
- </div>
-
-
<div id="paginator">
<div class=paginator>
diff --git a/archives/page/12/index.html b/archives/page/12/index.html
index 4c4718f9..30957190 100644
--- a/archives/page/12/index.html
+++ b/archives/page/12/index.html
@@ -145,6 +145,24 @@
<div class="post-list-item">
<div class="post-title">
+ <a href="/2022/11/03/%E4%BA%8C%E9%9B%B6%E4%BA%8C%E4%BA%8C%E5%B9%B4%E5%8D%81%E4%B8%80%E6%9C%88%E6%9C%88%E4%B8%89%E6%97%A5/">
+
+ 二零二二年十一月月三日
+
+ </a>
+ </div>
+
+ <span class="post-date">Nov 3, 2022</span>
+ </div>
+
+
+
+
+
+
+
+ <div class="post-list-item">
+ <div class="post-title">
<a href="/2022/10/01/%E4%BA%8C%E9%9B%B6%E4%BA%8C%E4%BA%8C%E5%B9%B4%E5%8D%81%E6%9C%88%E4%B8%80%E6%97%A5/">
二零二二年十月一日
@@ -302,26 +320,6 @@
</div>
-
-
-
-
- <div class="year-title">2020</div>
-
-
- <div class="post-list-item">
- <div class="post-title">
- <a href="/2020/12/26/%E4%BA%8C%E9%9B%B6%E4%BA%8C%E9%9B%B6%E5%B9%B4%E5%8D%81%E4%BA%8C%E6%9C%88%E4%BA%8C%E5%8D%81%E5%85%AD%E6%97%A5/">
-
- 二零二零年十二月二十六日
-
- </a>
- </div>
-
- <span class="post-date">Dec 26, 2020</span>
- </div>
-
-
<div id="paginator">
<div class=paginator>
diff --git a/archives/page/13/index.html b/archives/page/13/index.html
index 100c8d67..4c5b0b22 100644
--- a/archives/page/13/index.html
+++ b/archives/page/13/index.html
@@ -145,6 +145,24 @@
<div class="post-list-item">
<div class="post-title">
+ <a href="/2020/12/26/%E4%BA%8C%E9%9B%B6%E4%BA%8C%E9%9B%B6%E5%B9%B4%E5%8D%81%E4%BA%8C%E6%9C%88%E4%BA%8C%E5%8D%81%E5%85%AD%E6%97%A5/">
+
+ 二零二零年十二月二十六日
+
+ </a>
+ </div>
+
+ <span class="post-date">Dec 26, 2020</span>
+ </div>
+
+
+
+
+
+
+
+ <div class="post-list-item">
+ <div class="post-title">
<a href="/2020/12/09/%E4%BA%8C%E9%9B%B6%E4%BA%8C%E9%9B%B6%E5%B9%B4%E5%8D%81%E4%BA%8C%E6%9C%88%E4%B9%9D%E6%97%A5/">
二零二零年十二月九日
diff --git a/archives/page/2/index.html b/archives/page/2/index.html
index e9ff33f5..9db6bf26 100644
--- a/archives/page/2/index.html
+++ b/archives/page/2/index.html
@@ -145,6 +145,24 @@
<div class="post-list-item">
<div class="post-title">
+ <a href="/2025/02/24/%E4%BA%8C%E3%80%87%E4%BA%8C%E4%BA%94%E5%B9%B4%E4%BA%8C%E6%9C%88%E4%BA%8C%E5%8D%81%E5%9B%9B%E6%97%A5/">
+
+ 二〇二五年二月二十四日
+
+ </a>
+ </div>
+
+ <span class="post-date">Feb 24, 2025</span>
+ </div>
+
+
+
+
+
+
+
+ <div class="post-list-item">
+ <div class="post-title">
<a href="/2025/02/19/Repository-pattern-in-Typescript/">
Repository pattern in Typescript
@@ -302,24 +320,6 @@
</div>
-
-
-
-
-
- <div class="post-list-item">
- <div class="post-title">
- <a href="/2024/11/15/%E8%A5%BF%E6%9F%9A%E5%AF%B9%E8%8D%AF%E7%89%A9%E7%9A%84%E5%BD%B1%E5%93%8D/">
-
- 西柚对药物的影响
-
- </a>
- </div>
-
- <span class="post-date">Nov 15, 2024</span>
- </div>
-
-
<div id="paginator">
<div class=paginator>
diff --git a/archives/page/3/index.html b/archives/page/3/index.html
index 18d9c5a7..483732c8 100644
--- a/archives/page/3/index.html
+++ b/archives/page/3/index.html
@@ -145,6 +145,24 @@
<div class="post-list-item">
<div class="post-title">
+ <a href="/2024/11/15/%E8%A5%BF%E6%9F%9A%E5%AF%B9%E8%8D%AF%E7%89%A9%E7%9A%84%E5%BD%B1%E5%93%8D/">
+
+ 西柚对药物的影响
+
+ </a>
+ </div>
+
+ <span class="post-date">Nov 15, 2024</span>
+ </div>
+
+
+
+
+
+
+
+ <div class="post-list-item">
+ <div class="post-title">
<a href="/2024/10/18/10-Tips-for-Productive-FSharp-Scripting/">
10 Tips for Productive FSharp Scripting
@@ -300,24 +318,6 @@
</div>
-
-
-
-
-
- <div class="post-list-item">
- <div class="post-title">
- <a href="/2024/09/08/%E4%B8%AD%E8%80%81%E5%B9%B4%E4%BA%BA%E6%B2%89%E8%BF%B7%E6%89%8B%E6%9C%BA%E7%9A%84%E9%97%AE%E9%A2%98/">
-
- 中老年人沉迷手机的问题
-
- </a>
- </div>
-
- <span class="post-date">Sep 8, 2024</span>
- </div>
-
-
<div id="paginator">
<div class=paginator>
diff --git a/archives/page/4/index.html b/archives/page/4/index.html
index c7eb68c3..e3a9d213 100644
--- a/archives/page/4/index.html
+++ b/archives/page/4/index.html
@@ -145,6 +145,24 @@
<div class="post-list-item">
<div class="post-title">
+ <a href="/2024/09/08/%E4%B8%AD%E8%80%81%E5%B9%B4%E4%BA%BA%E6%B2%89%E8%BF%B7%E6%89%8B%E6%9C%BA%E7%9A%84%E9%97%AE%E9%A2%98/">
+
+ 中老年人沉迷手机的问题
+
+ </a>
+ </div>
+
+ <span class="post-date">Sep 8, 2024</span>
+ </div>
+
+
+
+
+
+
+
+ <div class="post-list-item">
+ <div class="post-title">
<a href="/2024/09/07/%E7%BB%99%E5%AD%A9%E5%AD%90%E4%BB%AC%E7%9A%84%E8%AF%9D/">
什么玩意儿都是
@@ -300,24 +318,6 @@
</div>
-
-
-
-
-
- <div class="post-list-item">
- <div class="post-title">
- <a href="/2024/06/27/OCaml-News-2024-5/">
-
- OCaml News 2024-5
-
- </a>
- </div>
-
- <span class="post-date">Jun 27, 2024</span>
- </div>
-
-
<div id="paginator">
<div class=paginator>
diff --git a/archives/page/5/index.html b/archives/page/5/index.html
index 29419e15..2e114be2 100644
--- a/archives/page/5/index.html
+++ b/archives/page/5/index.html
@@ -145,6 +145,24 @@
<div class="post-list-item">
<div class="post-title">
+ <a href="/2024/06/27/OCaml-News-2024-5/">
+
+ OCaml News 2024-5
+
+ </a>
+ </div>
+
+ <span class="post-date">Jun 27, 2024</span>
+ </div>
+
+
+
+
+
+
+
+ <div class="post-list-item">
+ <div class="post-title">
<a href="/2024/06/06/NET-AOT-%E4%B8%8B%E7%9A%84-F-%E5%91%BD%E4%BB%A4%E8%A1%8C%E5%8F%82%E6%95%B0%E8%A7%A3%E6%9E%90%E5%BA%93%E9%80%89%E6%8B%A9/">
.NET AOT 下的 F# 命令行参数解析库选择
@@ -300,24 +318,6 @@
</div>
-
-
-
-
-
- <div class="post-list-item">
- <div class="post-title">
- <a href="/2024/02/07/%E4%BA%8C%E3%80%87%E4%BA%8C%E5%9B%9B%E5%B9%B4%E4%BA%8C%E6%9C%88%E4%B8%83%E6%97%A5/">
-
- 二〇二四年二月七日
-
- </a>
- </div>
-
- <span class="post-date">Feb 7, 2024</span>
- </div>
-
-
<div id="paginator">
<div class=paginator>
diff --git a/archives/page/6/index.html b/archives/page/6/index.html
index e291cb8a..e95970d6 100644
--- a/archives/page/6/index.html
+++ b/archives/page/6/index.html
@@ -145,6 +145,24 @@
<div class="post-list-item">
<div class="post-title">
+ <a href="/2024/02/07/%E4%BA%8C%E3%80%87%E4%BA%8C%E5%9B%9B%E5%B9%B4%E4%BA%8C%E6%9C%88%E4%B8%83%E6%97%A5/">
+
+ 二〇二四年二月七日
+
+ </a>
+ </div>
+
+ <span class="post-date">Feb 7, 2024</span>
+ </div>
+
+
+
+
+
+
+
+ <div class="post-list-item">
+ <div class="post-title">
<a href="/2024/01/25/%E6%80%A5%E8%AF%8A%E4%B8%8E%E7%81%BE%E9%9A%BE%E5%8C%BB%E5%AD%A6-%E7%83%A7%E4%BC%A4/">
急诊与灾难医学--烧伤
@@ -302,24 +320,6 @@
</div>
-
-
-
-
-
- <div class="post-list-item">
- <div class="post-title">
- <a href="/2023/11/29/%E4%BA%8C%E3%80%87%E4%BA%8C%E4%B8%89%E5%B9%B4%E5%8D%81%E4%B8%80%E6%9C%88%E4%BA%8C%E5%8D%81%E4%B9%9D%E6%97%A5/">
-
- 二〇二三年十一月二十九日
-
- </a>
- </div>
-
- <span class="post-date">Nov 29, 2023</span>
- </div>
-
-
<div id="paginator">
<div class=paginator>
diff --git a/archives/page/7/index.html b/archives/page/7/index.html
index 4610faf7..6cf70470 100644
--- a/archives/page/7/index.html
+++ b/archives/page/7/index.html
@@ -145,6 +145,24 @@
<div class="post-list-item">
<div class="post-title">
+ <a href="/2023/11/29/%E4%BA%8C%E3%80%87%E4%BA%8C%E4%B8%89%E5%B9%B4%E5%8D%81%E4%B8%80%E6%9C%88%E4%BA%8C%E5%8D%81%E4%B9%9D%E6%97%A5/">
+
+ 二〇二三年十一月二十九日
+
+ </a>
+ </div>
+
+ <span class="post-date">Nov 29, 2023</span>
+ </div>
+
+
+
+
+
+
+
+ <div class="post-list-item">
+ <div class="post-title">
<a href="/2023/11/21/Adolescent-Onset-of-Acute-Heart-Failure/">
Adolescent Onset of Acute Heart Failure
@@ -300,24 +318,6 @@
</div>
-
-
-
-
-
- <div class="post-list-item">
- <div class="post-title">
- <a href="/2023/10/12/%E8%A1%80%E5%B8%B8%E8%A7%84%E5%8C%96%E9%AA%8C%E7%BB%93%E6%9E%9C%E9%98%85%E8%AF%BB%E6%8C%87%E5%8D%97/">
-
- 血常规化验结果阅读指南
-
- </a>
- </div>
-
- <span class="post-date">Oct 12, 2023</span>
- </div>
-
-
<div id="paginator">
<div class=paginator>
diff --git a/archives/page/8/index.html b/archives/page/8/index.html
index 34dbf781..00eafe71 100644
--- a/archives/page/8/index.html
+++ b/archives/page/8/index.html
@@ -145,6 +145,24 @@
<div class="post-list-item">
<div class="post-title">
+ <a href="/2023/10/12/%E8%A1%80%E5%B8%B8%E8%A7%84%E5%8C%96%E9%AA%8C%E7%BB%93%E6%9E%9C%E9%98%85%E8%AF%BB%E6%8C%87%E5%8D%97/">
+
+ 血常规化验结果阅读指南
+
+ </a>
+ </div>
+
+ <span class="post-date">Oct 12, 2023</span>
+ </div>
+
+
+
+
+
+
+
+ <div class="post-list-item">
+ <div class="post-title">
<a href="/2023/10/12/%E8%BF%87%E5%BA%A6%E7%96%B2%E5%8A%B3%E7%9A%84%E5%85%AD%E7%A7%8D%E8%A1%A8%E7%8E%B0/">
过度疲劳的六种表现
@@ -300,24 +318,6 @@
</div>
-
-
-
-
-
- <div class="post-list-item">
- <div class="post-title">
- <a href="/2023/07/30/%E4%BA%8C%E9%9B%B6%E4%BA%8C%E4%B8%89%E5%B9%B4%E4%B8%83%E6%9C%88%E4%B8%89%E5%8D%81%E6%97%A5/">
-
- 二零二三年七月三十日
-
- </a>
- </div>
-
- <span class="post-date">Jul 30, 2023</span>
- </div>
-
-
<div id="paginator">
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diff --git a/archives/page/9/index.html b/archives/page/9/index.html
index b2ce4981..2bebf7b6 100644
--- a/archives/page/9/index.html
+++ b/archives/page/9/index.html
@@ -145,6 +145,24 @@
<div class="post-list-item">
<div class="post-title">
+ <a href="/2023/07/30/%E4%BA%8C%E9%9B%B6%E4%BA%8C%E4%B8%89%E5%B9%B4%E4%B8%83%E6%9C%88%E4%B8%89%E5%8D%81%E6%97%A5/">
+
+ 二零二三年七月三十日
+
+ </a>
+ </div>
+
+ <span class="post-date">Jul 30, 2023</span>
+ </div>
+
+
+
+
+
+
+
+ <div class="post-list-item">
+ <div class="post-title">
<a href="/2023/07/21/WiscKey-Separating-Keys-from-Values-in-SSD-conscious-Storage/">
WiscKey: Separating Keys from Values in SSD-conscious Storage
@@ -300,24 +318,6 @@
</div>
-
-
-
-
-
- <div class="post-list-item">
- <div class="post-title">
- <a href="/2023/05/02/Rust-Partial-%E8%AF%AD%E4%B9%89/">
-
- Rust Partial 语义
-
- </a>
- </div>
-
- <span class="post-date">May 2, 2023</span>
- </div>
-
-
<div id="paginator">
<div class=paginator>
diff --git a/page/8/index.html b/page/8/index.html
index 96926193..40df0132 100644
--- a/page/8/index.html
+++ b/page/8/index.html
@@ -59,7 +59,119 @@
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+ cursor: pointer;
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+ min-width: 25%;
+ padding: .2em .4em;
+ border: 1px solid #888;
+ font-size: 90%;
+ background-color: #F8F8F8;
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+</style></head>
<body>
<div class="mask-border">
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diff --git a/search.xml b/search.xml
index 13ae68b5..c81be945 100644
--- a/search.xml
+++ b/search.xml
@@ -824,6 +824,45 @@
</tags>
</entry>
<entry>
+ <title>N+1 selects problem 与 Prisma ORM</title>
+ <url>/2025/04/02/N-1-selects-problem-%E4%B8%8E-Prisma-ORM/</url>
+ <content><![CDATA[<p>N+1 查询问题是指在通过 ORM 查询数据时,执行了<strong>一次</strong>初始查询来获取父对象列表(这 <strong>1</strong> 次查询),然后为列表中的<strong>每一个</strong>父对象都单独执行了一次额外的查询来获取其关联的子对象(这 <strong>N</strong> 次查询)。最终导致总共执行了 <strong>1 + N</strong> 次数据库查询,其中 N 是初始查询返回的父对象的数量。</p>
+<p><strong>举个例子:</strong></p>
+<p>假设有两个数据库模型:<code>User</code>(用户)和 <code>Post</code>(帖子),一个用户可以有多篇帖子(一对多关系)。</p>
+<p>现在,需要获取前 10 个用户以及他们各自的所有帖子。</p>
+<p>一种<strong>有问题</strong>的 ORM 实现(或不当的使用方式)可能会这样执行:</p>
+<ol>
+<li><strong>第一次查询 (The “1”)</strong>: 获取前 10 个用户。<figure class="highlight sql"><table><tr><td class="code"><pre><span class="line"><span class="keyword">SELECT</span> <span class="operator">*</span> <span class="keyword">FROM</span> <span class="keyword">User</span> LIMIT <span class="number">10</span>;</span><br></pre></td></tr></table></figure></li>
+<li><strong>接下来的 N (&#x3D;10) 次查询 (The “N”)</strong>: 对于上一步获取到的每一个用户,单独执行一次查询来获取该用户的帖子。<figure class="highlight sql"><table><tr><td class="code"><pre><span class="line"><span class="comment">-- 用户 1</span></span><br><span class="line"><span class="keyword">SELECT</span> <span class="operator">*</span> <span class="keyword">FROM</span> Post <span class="keyword">WHERE</span> authorId <span class="operator">=</span> <span class="number">1</span>;</span><br><span class="line"><span class="comment">-- 用户 2</span></span><br><span class="line"><span class="keyword">SELECT</span> <span class="operator">*</span> <span class="keyword">FROM</span> Post <span class="keyword">WHERE</span> authorId <span class="operator">=</span> <span class="number">2</span>;</span><br><span class="line"><span class="comment">-- 用户 3</span></span><br><span class="line"><span class="keyword">SELECT</span> <span class="operator">*</span> <span class="keyword">FROM</span> Post <span class="keyword">WHERE</span> authorId <span class="operator">=</span> <span class="number">3</span>;</span><br><span class="line"><span class="comment">-- ... 直到 用户 10</span></span><br><span class="line"><span class="keyword">SELECT</span> <span class="operator">*</span> <span class="keyword">FROM</span> Post <span class="keyword">WHERE</span> authorId <span class="operator">=</span> <span class="number">10</span>;</span><br></pre></td></tr></table></figure></li>
+</ol>
+<p>在这个场景下,总共执行了 1 + 10 &#x3D; <strong>11</strong> 次数据库查询。如果 N 的值很大(比如获取 1000 个用户),就会产生 1001 次查询,这对数据库造成巨大的、不必要的压力,并显著增加应用程序的响应时间。每一次数据库交互都有网络延迟和数据库处理的开销,N+1 次查询会将这些开销放大 N 倍。</p>
+<p>N+1 问题通常源于 ORM 处理关联数据的方式,特别是与“懒加载”(Lazy Loading)相关的策略。懒加载是指只有在显式访问关联属性时,ORM 才会去数据库加载这些数据。虽然这在某些情况下可以避免加载不需要的数据,但如果在循环中访问关联属性,就很容易触发 N+1 问题。</p>
+<p>然而,问题的根源在于<strong>没有有效地预先加载(或批量加载)所需的关联数据</strong>。即使不使用严格意义上的懒加载,如果 ORM 在处理关联查询时不够智能,采用了逐个获取关联对象的策略,同样会产生 N+1 查询。</p>
+<p>在 Prisma 出现之前或在其他 ORM 中,解决 N+1 问题常见的方法包括:</p>
+<ol>
+<li><strong>预先加载(Eager Loading)</strong>: 在执行初始查询时,就明确指示 ORM 同时将关联数据也查询出来。这通常通过 SQL 的 <code>JOIN</code> 操作实现。例如,一次性查询出用户和他们的帖子。虽然这减少了查询次数,但复杂的 <code>JOIN</code> 可能会导致查询本身变得庞大和低效,并可能返回冗余数据。</li>
+<li><strong>批量加载(Batch Loading)</strong>: 先执行初始查询获取父对象列表,然后收集所有父对象的 ID,在第二次查询中使用 <code>WHERE IN (...)</code> 子句一次性加载所有相关的子对象。这种方式通常需要两次查询,但避免了 N 次单独的查询。</li>
+</ol>
+<p>Prisma ORM 在设计上就考虑了 N+1 问题,并提供了一种既方便开发者又高效的解决方案。当使用 Prisma Client 查询数据并需要包含关联模型时,Prisma 会自动优化查询,<strong>避免产生 N+1 查询</strong>,主要通过<strong>关系查询(Relation Queries)</strong>中的 <code>include</code> 选项或嵌套读取(nested reads)来实现这一点:</p>
+<p>假设想获取所有用户及其发布的帖子,使用 Prisma Client,可以这样写:</p>
+<figure class="highlight typescript"><table><tr><td class="code"><pre><span class="line"><span class="keyword">import</span> &#123; <span class="title class_">PrismaClient</span> &#125; <span class="keyword">from</span> <span class="string">&#x27;@prisma/client&#x27;</span></span><br><span class="line"></span><br><span class="line"><span class="keyword">const</span> prisma = <span class="keyword">new</span> <span class="title class_">PrismaClient</span>()</span><br><span class="line"></span><br><span class="line"><span class="keyword">async</span> <span class="keyword">function</span> <span class="title function_">getUsersWithPosts</span>(<span class="params"></span>) &#123;</span><br><span class="line"> <span class="keyword">const</span> usersWithPosts = <span class="keyword">await</span> prisma.<span class="property">user</span>.<span class="title function_">findMany</span>(&#123;</span><br><span class="line"> <span class="attr">include</span>: &#123;</span><br><span class="line"> <span class="attr">posts</span>: <span class="literal">true</span>, <span class="comment">// 指示 Prisma 加载关联的 posts</span></span><br><span class="line"> &#125;,</span><br><span class="line"> &#125;)</span><br><span class="line"> <span class="comment">// usersWithPosts 包含了用户列表,每个用户对象中都有一个 posts 数组</span></span><br><span class="line"> <span class="variable language_">console</span>.<span class="title function_">log</span>(usersWithPosts)</span><br><span class="line">&#125;</span><br><span class="line"></span><br><span class="line"><span class="title function_">getUsersWithPosts</span>()</span><br><span class="line"> .<span class="title function_">catch</span>(<span class="function">(<span class="params">e</span>) =&gt;</span> &#123;</span><br><span class="line"> <span class="keyword">throw</span> e</span><br><span class="line"> &#125;)</span><br><span class="line"> .<span class="title function_">finally</span>(<span class="keyword">async</span> () =&gt; &#123;</span><br><span class="line"> <span class="keyword">await</span> prisma.$disconnect()</span><br><span class="line"> &#125;)</span><br></pre></td></tr></table></figure>
+
+<p>当执行上述查询时,Prisma <strong>不会</strong> 生成 N+1 个 SQL 查询。而是首先会分析请求,并将其转化为数量非常有限的高效 SQL 查询。对于上面这个一对多关系的 <code>include</code> 查询,Prisma 通常会执行以下<strong>两步</strong>(类似于批量加载策略):</p>
+<ol>
+<li><strong>查询父模型</strong>: 获取所有 <code>User</code> 记录。<figure class="highlight sql"><table><tr><td class="code"><pre><span class="line"><span class="keyword">SELECT</span> &quot;public&quot;.&quot;User&quot;.&quot;id&quot;, &quot;public&quot;.&quot;User&quot;.&quot;name&quot;, <span class="comment">/* ... other user fields */</span> <span class="keyword">FROM</span> &quot;public&quot;.&quot;User&quot; <span class="keyword">WHERE</span> <span class="number">1</span><span class="operator">=</span><span class="number">1</span></span><br></pre></td></tr></table></figure></li>
+<li><strong>查询关联的子模型</strong>: 使用上一步获取到的所有用户 <code>id</code>,通过 <code>WHERE IN (...)</code> 子句一次性查询所有相关的 <code>Post</code> 记录。<figure class="highlight sql"><table><tr><td class="code"><pre><span class="line"><span class="keyword">SELECT</span> &quot;public&quot;.&quot;Post&quot;.&quot;id&quot;, &quot;public&quot;.&quot;Post&quot;.&quot;title&quot;, &quot;public&quot;.&quot;Post&quot;.&quot;authorId&quot;, <span class="comment">/* ... other post fields */</span> <span class="keyword">FROM</span> &quot;public&quot;.&quot;Post&quot; <span class="keyword">WHERE</span> &quot;public&quot;.&quot;Post&quot;.&quot;authorId&quot; <span class="keyword">IN</span> ($<span class="number">1</span>, $<span class="number">2</span>, $<span class="number">3</span>, ...) <span class="comment">/* 这里的 $1, $2, ... 是第一步查到的用户 ID 列表 */</span></span><br></pre></td></tr></table></figure></li>
+</ol>
+<p>Prisma Client 在内存中将这两次查询的结果高效地组合起来,最终返回嵌套的、符合 TypeScript 类型的数据。</p>
+<h2 id="Refs"><a href="#Refs" class="headerlink" title="Refs."></a>Refs.</h2><ul>
+<li><a href="https://stackoverflow.com/questions/97197/what-is-the-n1-selects-problem-in-orm-object-relational-mapping">Stack Overflow: What is the N+1 selects problem in ORM?</a></li>
+<li><a href="https://www.prisma.io/docs/orm/prisma-client/queries/query-optimization-performance#solving-the-n1-problem">Prisma Docs: Solving the N+1 problem</a></li>
+</ul>
+]]></content>
+ <tags>
+ <tag>Technique</tag>
+ </tags>
+ </entry>
+ <entry>
<title>.NET AOT 下的 F# 命令行参数解析库选择</title>
<url>/2024/06/06/NET-AOT-%E4%B8%8B%E7%9A%84-F-%E5%91%BD%E4%BB%A4%E8%A1%8C%E5%8F%82%E6%95%B0%E8%A7%A3%E6%9E%90%E5%BA%93%E9%80%89%E6%8B%A9/</url>
<content><![CDATA[<p>Argu 不支持 AOT,不过用 F# 的话可以看整个 .NET 的生态,我看了一下 C# 的 CommandLineParser:<br><a href="https://github.com/commandlineparser">https://github.com/commandlineparser</a></p>
@@ -3086,6 +3125,24 @@
</categories>
</entry>
<entry>
+ <title>二零二零年十二月九日</title>
+ <url>/2020/12/09/%E4%BA%8C%E9%9B%B6%E4%BA%8C%E9%9B%B6%E5%B9%B4%E5%8D%81%E4%BA%8C%E6%9C%88%E4%B9%9D%E6%97%A5/</url>
+ <content><![CDATA[<p>我们走在朝阳的洪流上, 一步一个脚印, 踏散阳光, 向南是北。</p>
+]]></content>
+ <categories>
+ <category>gallery</category>
+ </categories>
+ </entry>
+ <entry>
+ <title>二零二零年十二月二十六日</title>
+ <url>/2020/12/26/%E4%BA%8C%E9%9B%B6%E4%BA%8C%E9%9B%B6%E5%B9%B4%E5%8D%81%E4%BA%8C%E6%9C%88%E4%BA%8C%E5%8D%81%E5%85%AD%E6%97%A5/</url>
+ <content><![CDATA[<p>我被包裹在吊床中,两颗香樟树支撑着它,仲夏的热浪砸在粗壮的香樟树上,叶子一屈,抱住了热浪,可随即而来的是不知从哪浇来的阳光,叶子承受不住这样的力量,被砸的孔洞百出,砸的香气落满树下的人间。</p>
+]]></content>
+ <categories>
+ <category>gallery</category>
+ </categories>
+ </entry>
+ <entry>
<title>二零二零年十二月八日</title>
<url>/2020/12/08/%E4%BA%8C%E9%9B%B6%E4%BA%8C%E9%9B%B6%E5%B9%B4%E5%8D%81%E4%BA%8C%E6%9C%88%E5%85%AB%E6%97%A5/</url>
<content><![CDATA[<p>它们勇敢的站在烈日下, 像人类一样无所畏惧, 却又恐惧的躲在黑暗中, 像当初的它们一样无处可逃。</p>
@@ -5896,24 +5953,6 @@
</tags>
</entry>
<entry>
- <title>二零二零年十二月九日</title>
- <url>/2020/12/09/%E4%BA%8C%E9%9B%B6%E4%BA%8C%E9%9B%B6%E5%B9%B4%E5%8D%81%E4%BA%8C%E6%9C%88%E4%B9%9D%E6%97%A5/</url>
- <content><![CDATA[<p>我们走在朝阳的洪流上, 一步一个脚印, 踏散阳光, 向南是北。</p>
-]]></content>
- <categories>
- <category>gallery</category>
- </categories>
- </entry>
- <entry>
- <title>二零二零年十二月二十六日</title>
- <url>/2020/12/26/%E4%BA%8C%E9%9B%B6%E4%BA%8C%E9%9B%B6%E5%B9%B4%E5%8D%81%E4%BA%8C%E6%9C%88%E4%BA%8C%E5%8D%81%E5%85%AD%E6%97%A5/</url>
- <content><![CDATA[<p>我被包裹在吊床中,两颗香樟树支撑着它,仲夏的热浪砸在粗壮的香樟树上,叶子一屈,抱住了热浪,可随即而来的是不知从哪浇来的阳光,叶子承受不住这样的力量,被砸的孔洞百出,砸的香气落满树下的人间。</p>
-]]></content>
- <categories>
- <category>gallery</category>
- </categories>
- </entry>
- <entry>
<title>关于</title>
<url>/about.html</url>
<content><![CDATA[<h2 id="韩暮秋"><a href="#韩暮秋" class="headerlink" title="韩暮秋"></a>韩暮秋</h2><blockquote>
diff --git a/tags/Technique/index.html b/tags/Technique/index.html
index 2a98a9bb..f7bc09ba 100644
--- a/tags/Technique/index.html
+++ b/tags/Technique/index.html
@@ -152,6 +152,24 @@
<div class="post-list-item">
<div class="post-title">
+ <a href="/2025/04/02/N-1-selects-problem-%E4%B8%8E-Prisma-ORM/">
+
+ N+1 selects problem 与 Prisma ORM
+
+ </a>
+ </div>
+
+ <span class="post-date">Apr 2, 2025</span>
+ </div>
+
+
+
+
+
+
+
+ <div class="post-list-item">
+ <div class="post-title">
<a href="/2025/03/31/%E5%9C%A8F-%E4%B8%AD%E5%A4%84%E7%90%86%E5%A4%8D%E6%9D%82%E4%BE%9D%E8%B5%96%E6%B3%A8%E5%85%A5%E7%9A%84%E5%AE%9E%E8%B7%B5%E6%8C%87%E5%8D%97/">
在F#中处理复杂依赖注入的实践指南
@@ -307,24 +325,6 @@
</div>
-
-
-
-
-
- <div class="post-list-item">
- <div class="post-title">
- <a href="/2025/02/11/%E4%BB%8E%E4%BA%8B%E4%BB%B6%E9%A3%8E%E6%9A%B4%E7%9C%8B%E9%A2%86%E5%9F%9F%E9%A9%B1%E5%8A%A8%E8%AE%BE%E8%AE%A1/">
-
- 从事件风暴看领域驱动设计
-
- </a>
- </div>
-
- <span class="post-date">Feb 11, 2025</span>
- </div>
-
-
<div id="paginator">
<div class=paginator>
diff --git a/tags/Technique/page/2/index.html b/tags/Technique/page/2/index.html
index 614e0df7..b9b6d884 100644
--- a/tags/Technique/page/2/index.html
+++ b/tags/Technique/page/2/index.html
@@ -152,6 +152,24 @@
<div class="post-list-item">
<div class="post-title">
+ <a href="/2025/02/11/%E4%BB%8E%E4%BA%8B%E4%BB%B6%E9%A3%8E%E6%9A%B4%E7%9C%8B%E9%A2%86%E5%9F%9F%E9%A9%B1%E5%8A%A8%E8%AE%BE%E8%AE%A1/">
+
+ 从事件风暴看领域驱动设计
+
+ </a>
+ </div>
+
+ <span class="post-date">Feb 11, 2025</span>
+ </div>
+
+
+
+
+
+
+
+ <div class="post-list-item">
+ <div class="post-title">
<a href="/2025/02/10/%E5%AE%9E%E6%97%B6%E6%90%9C%E7%B4%A2%E4%B8%AD%E7%9A%84%E9%98%B2%E6%8A%96%E5%87%BD%E6%95%B0/">
实时搜索中的防抖函数
@@ -309,24 +327,6 @@
</div>
-
-
-
-
-
- <div class="post-list-item">
- <div class="post-title">
- <a href="/2024/07/23/OCaml-News-2024-6/">
-
- OCaml News 2024-6
-
- </a>
- </div>
-
- <span class="post-date">Jul 23, 2024</span>
- </div>
-
-
<div id="paginator">
<div class=paginator>
diff --git a/tags/Technique/page/3/index.html b/tags/Technique/page/3/index.html
index f6079531..76afb127 100644
--- a/tags/Technique/page/3/index.html
+++ b/tags/Technique/page/3/index.html
@@ -152,6 +152,24 @@
<div class="post-list-item">
<div class="post-title">
+ <a href="/2024/07/23/OCaml-News-2024-6/">
+
+ OCaml News 2024-6
+
+ </a>
+ </div>
+
+ <span class="post-date">Jul 23, 2024</span>
+ </div>
+
+
+
+
+
+
+
+ <div class="post-list-item">
+ <div class="post-title">
<a href="/2024/07/01/OCaml-News-2024-4/">
OCaml News 2024-4
@@ -307,24 +325,6 @@
</div>
-
-
-
-
-
- <div class="post-list-item">
- <div class="post-title">
- <a href="/2024/01/08/OCaml-News-2024-1/">
-
- OCaml News 2024-1
-
- </a>
- </div>
-
- <span class="post-date">Jan 8, 2024</span>
- </div>
-
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<div id="paginator">
<div class=paginator>
diff --git a/tags/Technique/page/4/index.html b/tags/Technique/page/4/index.html
index e982b92c..4ce2be67 100644
--- a/tags/Technique/page/4/index.html
+++ b/tags/Technique/page/4/index.html
@@ -147,6 +147,26 @@
+ <div class="year-title">2024</div>
+
+
+ <div class="post-list-item">
+ <div class="post-title">
+ <a href="/2024/01/08/OCaml-News-2024-1/">
+
+ OCaml News 2024-1
+
+ </a>
+ </div>
+
+ <span class="post-date">Jan 8, 2024</span>
+ </div>
+
+
+
+
+
+
<div class="year-title">2023</div>
@@ -307,24 +327,6 @@
</div>
-
-
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-
-
- <div class="post-list-item">
- <div class="post-title">
- <a href="/2023/05/03/Rust-NewType-%E6%A8%A1%E5%BC%8F/">
-
- Rust NewType 模式
-
- </a>
- </div>
-
- <span class="post-date">May 3, 2023</span>
- </div>
-
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<div id="paginator">
<div class=paginator>
diff --git a/tags/Technique/page/5/index.html b/tags/Technique/page/5/index.html
index 09b398ae..ccda6e55 100644
--- a/tags/Technique/page/5/index.html
+++ b/tags/Technique/page/5/index.html
@@ -152,6 +152,24 @@
<div class="post-list-item">
<div class="post-title">
+ <a href="/2023/05/03/Rust-NewType-%E6%A8%A1%E5%BC%8F/">
+
+ Rust NewType 模式
+
+ </a>
+ </div>
+
+ <span class="post-date">May 3, 2023</span>
+ </div>
+
+
+
+
+
+
+
+ <div class="post-list-item">
+ <div class="post-title">
<a href="/2023/05/02/Rust-Partial-%E8%AF%AD%E4%B9%89/">
Rust Partial 语义