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mysql_fetch_field

(PHP 3, PHP 4 )

mysql_fetch_field -- Get column information from a result and return as an object

Description

object mysql_fetch_field ( resource result [, int field_offset])

Returns an object containing field information.

mysql_fetch_field() can be used in order to obtain information about fields in a certain query result. If the field offset isn't specified, the next field that wasn't yet retrieved by mysql_fetch_field() is retrieved.

The properties of the object are:

name - column name
table - name of the table the column belongs to
max_length - maximum length of the column
not_null - 1 if the column cannot be NULL
primary_key - 1 if the column is a primary key
unique_key - 1 if the column is a unique key
multiple_key - 1 if the column is a non-unique key
numeric - 1 if the column is numeric
blob - 1 if the column is a BLOB
type - the type of the column
unsigned - 1 if the column is unsigned
zerofill - 1 if the column is zero-filled

Note: Field names returned by this function are case-sensitive.

Example 1. mysql_fetch_field() example

<?php

$conn = mysql_connect('localhost:3306', 'user', 'password');

if (!$conn) {

  die('Could not connect: ' . mysql_error());

}

mysql_select_db('database');

$result = mysql_query('select * from table');

if (!$result) {

  die('Query failed: ' . mysql_error());

}

/* get column metadata */

$i = 0;

while ($i < mysql_num_fields($result)) {

  echo "Information for column $i:
\n";

  $meta = mysql_fetch_field($result, $i);

  if (!$meta) {

    echo "No information available
\n";

  }

  echo "

blob:        $meta->blob

max_length:  $meta->max_length

multiple_key: $meta->multiple_key

name:        $meta->name

not_null:    $meta->not_null

numeric:      $meta->numeric

primary_key:  $meta->primary_key

table:        $meta->table

type:        $meta->type

unique_key:  $meta->unique_key

unsigned:    $meta->unsigned

zerofill:    $meta->zerofill

";

  $i++;

}

mysql_free_result($result);

?>