使用apcu_exists时常见哪些逻辑错误？如何避免这些问题？

<span><span><span class="hljs-meta"><?php</span></span><span>
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</span><span><span class="hljs-keyword">echo</span></span><span> </span><span><span class="hljs-string">"这是程序启动信息\n"</span></span><span>;
</span><span><span class="hljs-title function_ invoke__">date_default_timezone_set</span></span><span>(</span><span><span class="hljs-string">'Asia/Shanghai'</span></span><span>);
</span><span><span class="hljs-variable">$startTime</span></span><span> = </span><span><span class="hljs-title function_ invoke__">microtime</span></span><span>(</span><span><span class="hljs-literal">true</span></span><span>);
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</span><span><span class="hljs-keyword">echo</span></span><span> </span><span><span class="hljs-string">"<h1>使用apcu_exists时常见哪些逻辑错误？如何避免这些问题？</h1>"</span></span><span>;

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</span><span><span class="hljs-keyword">echo</span></span><span> </span><span><span class="hljs-string">"<p>APCu是PHP中用于内存缓存的扩展，它提供了缓存键值对的功能。其中，<code>apcu_exists()