mysql_fetch_field

Function name: mysql_fetch_field()

Applicable version: PHP 4, PHP 5, PHP 7

Usage: The mysql_fetch_field() function is used to obtain information about fields from the result set.

grammar:

 mixed mysql_fetch_field ( resource $result [, int $field_offset = 0 ] )

parameter:

• result: Required. A MySQL result set resource.
• field_offset: optional. An integer representing the offset of the field. The default is 0, indicating the first field.

Return value:

• If successful, return an object containing the information of the field.
• If there is a failure or there are no more fields available, return false.

Example:

 // 创建数据库连接$conn = mysql_connect("localhost", "username", "password"); mysql_select_db("database_name", $conn); // 执行查询$result = mysql_query("SELECT * FROM table_name", $conn); // 获取第一个字段的信息$field = mysql_fetch_field($result, 0); // 打印字段信息echo "字段名：" . $field->name . "<br>"; echo "字段类型：" . $field->type . "<br>"; echo "字段长度：" . $field->length . "<br>"; echo "字段标志：" . $field->flags . "<br>"; echo "字段自动增长：" . $field->flags . "<br>"; // 释放结果集mysql_free_result($result); // 关闭数据库连接mysql_close($conn);

Notes:

• Since the mysql extension is removed in PHP 7.0.0, it is recommended to use the mysqli or PDO_MySQL extension instead. Therefore, it is recommended to use the mysqli_fetch_field() function instead of the mysql_fetch_field() function.
• After PHP 5.5.0, the mysql_fetch_field() function has been marked as deprecated and has been removed in PHP 7.0.0. It is recommended to upgrade to mysqli or PDO_MySQL extension to get field information.