PHP mysqli_fetch_field_direct()Function

PHP MySQLi 参考手册PHP MySQLi Reference Manual

Return the meta-data of a single field (column) in a result set, and output the field name, table, and maximum length:

<?php 
// 假定数据库用户名：root，密码：123456，数据库：EXAMPLE 
$con=mysqli_connect("localhost","root","123456","EXAMPLE"); 
if (mysqli_connect_errno($con)) 
{ 
    echo "连接 MySQL 失败: " . mysqli_connect_error(); 
} 

$sql="SELECT name,url FROM websites ORDER BY alexa";


if ($result=mysqli_query($con,$sql))
{
// 获取字段 "name" 的信息
$fieldinfo=mysqli_fetch_field_direct($result,1);

printf("字段名: %s",$fieldinfo->name);
echo "<br>";
printf("数据表: %s",$fieldinfo->table);
echo "<br>";
printf("最大长度: %d",$fieldinfo->max_length);

// 释放结果集
mysqli_free_result($result);
}

mysqli_close($con);
?>

Definition and Usage

The mysqli_fetch_field_direct() function retrieves the meta-data of a single field (column) from a result set and returns it as an object.

Syntax

mysqli_fetch_field_direct(result,fieldnr);

Parameters Description
result Required. Specifies the result set identifier returned by mysqli_query(), mysqli_store_result(), or mysqli_use_result().
fieldnr Required. Specifies the field number. Must be between 0 and the number of fields minus 1.

Technical Details

Return value: Returns an object containing field definition information. Returns FALSE if no information is available. The object has the following properties:
  • name - The column name
  • orgname - The original column name (if an alias was specified)
  • table - The table name
  • orgtable - The original table name (if an alias was specified)
  • def - The default value of this field
  • max_length - The maximum width of the field
  • length - The field width as specified in the table definition
  • charsetnr - The character set number of the field
  • flags - The bit flags of the field
  • type - The data type used for the field
  • decimals - For integer fields, the number of digits after the decimal point
PHP version: 5+

PHP MySQLi 参考手册PHP MySQLi Reference Manual Other Extensions