`mysql_fetch_field`

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

Description

object mysql_fetch_field(resource result,


int field_offset= =0);

Returns an object containing field information. This function can be used to obtain information about fields in the provided query result.

Parameters

result: The result resource that is being evaluated. This result comes from a call to mysql_query.
field_offset: The numerical field offset. If the field offset is not specified, the next field that was not yet retrieved by this function is retrieved. The field_offset starts at 0.

Return Values

Returns an object containing field information. 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

Examples

Example 20.36. mysql_fetch_field example

<?php
$conn = mysql_connect('localhost', 'mysql_user', 'mysql_password');
if (!$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:<br />\n';
 $meta = mysql_fetch_field($result, $i);
 if (!$meta) {
 echo 'No information available<br />\n';
 }
 echo '<pre>
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
</pre>';
 $i++;
}
mysql_free_result($result);
?>

Notes

Note

Field names returned by this function are case-sensitive.