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HomeBackend DevelopmentPHP TutorialTips on using functions related to getting field length in PHP_PHP tutorial


Tips for using functions related to getting field length in PHP_PHP Tutorial

As a qualified

when designing a database, Because the data meaning represented by each field is different, the length of each field will not be exactly the same. In PHP, the mysql_field_len() function can be used to obtain the field length in PHP. The syntax format of this function is as follows:

int mysql_field_len ( resource $result, int $field_offset )

The parameters involved in the above syntax are described as follows.

l result:mysql_query()函数执行后返回的结果集。
l field_offset:字段的偏移量,起始值为零。

The sample code for PHP to get the field length using the mysql_field_len() function is as follows:

<ol class="dp-xml list-paddingleft-2">
<li><p><span class="tag"> ?php  </span></p></li>
<li><p>$<span class="attribute">connection</span>=<span class="attribute-value">mysql_connect</span>("localhost",<br>"root","root") or die("连接服务器失败");  </p></li>
<li><p>mysql_select_db("sunyang",$connection)<br> or die("选择数据库失败");  </p></li>
<li><p>$<span class="attribute">query</span>=<span class="attribute-value">"select * from employee"</span>;  </p></li>
<li><p>$<span class="attribute">result</span>=<span class="attribute-value">mysql_query</span>($query) or die<br>("查询数据失败"); //执行查询  </p></li>
<li><p>echo mysql_field_len($result, 0); <br>//第一个字段的长度  </p></li>
<li><p>echo mysql_field_len($result, 1); <br>//第二个字段的长度  </p></li>
<li><p>echo mysql_field_len($result, 2); <br>//第三个字段的长度  </p></li>
<li><p>echo mysql_field_len($result, 3);<br> //第四个字段的长度  </p></li>
<li><p>mysql_free_result($result);  </p></li>
<li><p>mysql_close();  </p></li>
<li><p><span class="tag">?></span>  </p></li>
</ol>


The above is the PHP to get the field length Related methods are explained. For more related content, please pay attention to the PHP Chinese website (www.php.cn)!



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