


In-depth discussion of the specific ways to delete database tables in PHP_PHP Tutorial
When we update and maintain the website, it may be a headache to delete the same database table. Today we will explain to you in detailThe specific implementation code of deleting the database table in PHP is as follows
<ol class="dp-xml"> <li class="alt"><span><span>function deldata($dbname,$tableflag){ </span></span></li> <li> <span>$</span><span class="attribute">db_host</span><span> = </span><span class="attribute-value">'localhost'</span><span>; </span> </li> <li class="alt"> <span>$</span><span class="attribute">db_port</span><span> = </span><span class="attribute-value">'3306'</span><span>; </span> </li> <li> <span>$</span><span class="attribute">db_user</span><span> = </span><span class="attribute-value">'user'</span><span>; </span> </li> <li class="alt"> <span>$</span><span class="attribute">db_pass</span><span> = </span><span class="attribute-value">'password'</span><span>; </span> </li> <li> <span>$</span><span class="attribute">connect</span><span> =</span><span class="attribute-value">mysql_connect</span><span>($db_host,$db_user,$db_pass); </span> </li> <li class="alt"><span>mysql_select_db($dbname); </span></li> <li> <span>$</span><span class="attribute">result</span><span> = </span><span class="attribute-value">mysql_query</span><span>("show table status from $dbname",$connect); </span> </li> <li class="alt"> <span>$</span><span class="attribute">data</span><span>=</span><span class="attribute-value">mysql_fetch_array</span><span>($result); </span> </li> <li> <span>while($</span><span class="attribute">data</span><span>=</span><span class="attribute-value">mysql_fetch_array</span><span>($result)) { </span> </li> <li class="alt"> <span>$</span><span class="attribute">table</span><span>=</span><span class="attribute-value">mysubstr</span><span>($data[Name],"_"); </span> </li> <li> <span>if($</span><span class="attribute">table</span><span>==$tableflag){ </span> </li> <li class="alt"><span>//测试之用 </span></li> <li><span>/*echo $data[Name]; </span></li> <li class="alt"><span> echo " </span></li> <li><span>"; </span></li> <li class="alt"><span> echo $table; </span></li> <li><span> echo " </span></li> <li class="alt"><span>";*/ </span></li> <li><span>mysql_query("drop table $data[Name]"); </span></li> <li class="alt"><span>} </span></li> <li><span>} </span></li> <li class="alt"><span>return true; </span></li> <li><span>} </span></li> <li class="alt"><span>/*截取某个特定字符前的所有字符函数 </span></li> <li><span>*$str 为待截取字符串 </span></li> <li class="alt"><span>*$flag 特定字符如“_” </span></li> <li><span>*/ </span></li> <li class="alt"><span>function mysubstr($str,$flag){ </span></li> <li> <span>$</span><span class="attribute">pos</span><span>=</span><span class="attribute-value">strpos</span><span>($str,$flag); </span> </li> <li class="alt"><span>return substr($str,0,$pos); </span></li> <li><span>} </span></li> <li class="alt"> <span class="tag">?></span><span> </span> </li> </ol>
<ol class="dp-xml"> <li class="alt"><span><span>$</span><span class="attribute">dbname</span><span>=</span><span class="attribute-value">"shujukuming"</span><span>;//数据库名 </span></span></li> <li> <span>$</span><span class="attribute">tableflag</span><span>=</span><span class="attribute-value">"xx"</span><span>;//要删除的表的前缀,有这个前缀的表才删除,标志出是哪一个用户 </span> </li> <li class="alt"><span>deldata($dbname,$tableflag); </span></li> <li> <span>//$</span><span class="attribute">test</span><span>=</span><span class="attribute-value">mysubstr</span><span>("cdb_account_log","_"); </span> </li> <li class="alt"><span>//echo $test; </span></li> <li> <span class="tag">?></span><span> </span> </li> </ol>
The changes in the database table deleted by PHP are:
1. At the beginning
<ol class="dp-xml"> <li class="alt"><span><span>function deldata($dbname,$tableflag){ </span></span></li> <li> <span>$</span><span class="attribute">db_host</span><span> = </span><span class="attribute-value">'localhost'</span><span>; </span> </li> <li class="alt"> <span>$</span><span class="attribute">db_port</span><span> = </span><span class="attribute-value">'3306'</span><span>; </span> </li> <li> <span>$</span><span class="attribute">db_user</span><span> = </span><span class="attribute-value">'user'</span><span>; </span> </li> <li class="alt"> <span>$</span><span class="attribute">db_pass</span><span> = </span><span class="attribute-value">'password'</span><span>; </span> </li> </ol>
Change it to your own database address, account number and password
2. At the end
<ol class="dp-xml"> <li class="alt"><span><span>$</span><span class="attribute">dbname</span><span>=</span><span class="attribute-value">"shujukuming"</span><span>;//数据库名 </span></span></li> <li> <span>$</span><span class="attribute">tableflag</span><span>=</span><span class="attribute-value">"xx"</span><span>;//要删除的表的前缀,有这个前缀的表才删除,标志出是哪一个用户 </span> </li> <li class="alt"><span>deldata($dbname,$tableflag); </span></li> <li> <span>//$</span><span class="attribute">test</span><span>=</span><span class="attribute-value">mysubstr</span><span>("cdb_account_log","_"); </span> </li> <li class="alt"><span>//echo $test; </span></li> <li> <span class="tag">?></span><span> </span> </li> <li class="alt"><span> </span></li> </ol>
Change it to your own database name and what you want to delete By removing the table prefix, PHP can complete deleting the database table.
You can copy the above code and save it as .php, then upload it to the space directory to open it
It is recommended to download this .php file http://flysh.toypark.in//up/1255275586.umd and change the suffix to php, just pick the name yourself and then upload it and open it.

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