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diff --git a/2024/09/11/MySQL11/index.html b/2024/09/11/MySQL11/index.html
@@ -412,10 +412,10 @@ <h1 class="description center-align post-title">怎么给字符串字段加索
 <figure class="highlight plaintext"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line">select id,name,email from SUser where email=&#x27;[email protected]&#x27;;</span><br></pre></td></tr></table></figure>
 
 <p><strong>如果使用的是index1</strong>（即email整个字符串的索引结构），执行顺序是这样的：</p>
-<p>1.<br>   从index1<strong>索引树</strong>找到满足索引值是’<a href="mailto:&#122;&#x68;&#x61;&#x6e;&#103;&#x73;&#115;&#120;&#121;&#x7a;&#x40;&#120;&#x78;&#x78;&#x2e;&#99;&#111;&#x6d;">&#122;&#x68;&#x61;&#x6e;&#103;&#x73;&#115;&#120;&#121;&#x7a;&#x40;&#120;&#x78;&#x78;&#x2e;&#99;&#111;&#x6d;</a>’的这条记录，取得ID2的值；<br>2. <strong>到主键上查到主键值是ID2的行，判断email的值是正确的，将这行记录加入结果集；</strong><br>3. <strong>取index1索引树上刚刚查到的位置的下一条记录，发现已经不满足email&#x3D;‘<a href="mailto:&#x7a;&#x68;&#97;&#110;&#x67;&#115;&#115;&#120;&#x79;&#122;&#64;&#120;&#x78;&#x78;&#46;&#x63;&#111;&#109;">&#x7a;&#x68;&#97;&#110;&#x67;&#115;&#115;&#120;&#x79;&#122;&#64;&#120;&#x78;&#x78;&#46;&#x63;&#111;&#109;</a>’的条件了，循环结束。</strong></p>
+<p>1.<br>   从index1<strong>索引树</strong>找到满足索引值是’<a href="mailto:&#122;&#x68;&#x61;&#x6e;&#103;&#x73;&#115;&#x78;&#121;&#122;&#64;&#120;&#120;&#120;&#x2e;&#99;&#111;&#109;">&#122;&#x68;&#x61;&#x6e;&#103;&#x73;&#115;&#x78;&#121;&#122;&#64;&#120;&#120;&#120;&#x2e;&#99;&#111;&#109;</a>’的这条记录，取得ID2的值；<br>2. <strong>到主键上查到主键值是ID2的行，判断email的值是正确的，将这行记录加入结果集；</strong><br>3. <strong>取index1索引树上刚刚查到的位置的下一条记录，发现已经不满足email&#x3D;‘<a href="mailto:&#122;&#104;&#97;&#x6e;&#x67;&#x73;&#115;&#120;&#121;&#x7a;&#x40;&#120;&#120;&#x78;&#x2e;&#x63;&#x6f;&#109;">&#122;&#104;&#97;&#x6e;&#x67;&#x73;&#115;&#120;&#121;&#x7a;&#x40;&#120;&#120;&#x78;&#x2e;&#x63;&#x6f;&#109;</a>’的条件了，循环结束。</strong></p>
 <p>这个过程中，<strong>只需要回主键索引取一次数据，所以系统认为只扫描了一行。</strong></p>
 <p><strong>如果使用的是index2</strong>（即email(6)索引结构），执行顺序是这样的：</p>
-<p>1.<br>   从index2索引树找到满足索引值是’zhangs’的记录，找到的第一个是ID1；<br>2. 到主键上查到主键值是ID1的行，判断出email的值不是’<a href="mailto:&#x7a;&#104;&#97;&#x6e;&#x67;&#115;&#115;&#120;&#121;&#x7a;&#x40;&#120;&#120;&#x78;&#46;&#99;&#111;&#x6d;">&#x7a;&#104;&#97;&#x6e;&#x67;&#115;&#115;&#120;&#121;&#x7a;&#x40;&#120;&#120;&#x78;&#46;&#99;&#111;&#x6d;</a>’，这行记录丢弃；<br>3. 取index2上刚刚查到的位置的下一条记录，发现仍然是’zhangs’，取出ID2，再到ID索引上取整行然后判断，这次值对了，将这行记录加入结果集；<br>4. 重复上一步，直到在idxe2上取到的值不是’zhangs’时，循环结束。</p>
+<p>1.<br>   从index2索引树找到满足索引值是’zhangs’的记录，找到的第一个是ID1；<br>2. 到主键上查到主键值是ID1的行，判断出email的值不是’<a href="mailto:&#122;&#x68;&#97;&#x6e;&#x67;&#x73;&#x73;&#x78;&#121;&#x7a;&#x40;&#x78;&#x78;&#120;&#x2e;&#x63;&#111;&#109;">&#122;&#x68;&#97;&#x6e;&#x67;&#x73;&#x73;&#x78;&#121;&#x7a;&#x40;&#x78;&#x78;&#120;&#x2e;&#x63;&#111;&#109;</a>’，这行记录丢弃；<br>3. 取index2上刚刚查到的位置的下一条记录，发现仍然是’zhangs’，取出ID2，再到ID索引上取整行然后判断，这次值对了，将这行记录加入结果集；<br>4. 重复上一步，直到在idxe2上取到的值不是’zhangs’时，循环结束。</p>
 <p><strong>在这个过程中，要回主键索引取4次数据，也就是扫描了4行。</strong></p>
 <p>通过这个对比，你很容易就可以发现，<strong>使用前缀索引后，可能会导致查询语句读数据的次数变多</strong>。</p>
 <p>但是，对于这个查询语句来说，<strong>如果你定义的index2不是email(6)而是email(7），也就是说取email字段的前7个字节来构建索引的话，即满足前缀’zhangss’的记录只有一个，也能够直接查到ID2，只扫描一行就结束了</strong>。</p>

diff --git a/2024/09/19/CPP02/index.html b/2024/09/19/CPP02/index.html
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