# 函数 ``` <pre class="calibre18">``` <span class="token6">1</span>、<span class="token4">version</span><span class="token3">(</span><span class="token3">)</span>　　MYsql版本 <span class="token6">2</span>、<span class="token4">user</span><span class="token3">(</span><span class="token3">)</span>　　 数据库用户名 <span class="token6">3</span>、<span class="token4">database</span><span class="token3">(</span><span class="token3">)</span> 数据库名 <span class="token6">4</span>、@@datadir 数据库路径 <span class="token6">5</span>、@@version_compile_os 操作系统版本 <span class="token6">6</span>、<span class="token4">current_user</span><span class="token3">(</span><span class="token3">)</span> 当前用户名（可查看权限） <span class="token6">7</span>、<span class="token4">load_file</span><span class="token3">(</span><span class="token3">)</span> 读文件 <span class="token6">8</span>、into <span class="token4">outfile</span><span class="token3">(</span><span class="token3">)</span> <span class="token1">/</span> into dumpfile 写文件 <span class="token6">9</span>、<span class="token4">group_concat</span><span class="token3">(</span>str1<span class="token3">,</span>str2<span class="token3">.</span><span class="token3">.</span><span class="token3">.</span><span class="token3">)</span> 连接一个组所有的字符串，并以逗号分隔每一条数据。 <span class="token4">concat_ws</span><span class="token3">(</span><span class="token2">','</span><span class="token3">,</span><span class="token6">1</span><span class="token3">,</span><span class="token6">2</span><span class="token3">,</span><span class="token6">3</span><span class="token3">)</span><span class="token3">;</span><span class="token">//指定第一个参数为连接符号，连接字符窜</span> <span class="token4">concat</span><span class="token3">(</span><span class="token2">'a'</span><span class="token3">,</span><span class="token2">'b'</span><span class="token3">,</span><span class="token6">1</span><span class="token3">)</span><span class="token3">;</span><span class="token">//连接字符串</span> ``` ``` # [URL编码对照表](https://blog.csdn.net/sinat_34439107/article/details/78242584) php字符换与url编码的转换 ``` <pre class="calibre17">``` <span class="token4">urlencode</span><span class="token3">(</span>$url<span class="token3">)</span> 转url编码 <span class="token4">urldecode</span><span class="token3">(</span>$url<span class="token3">)</span> 解析url编码 ``` ```