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(PHP 3, PHP 4 )

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


object mysql_fetch_field (int 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

Example 1. Mysql_fetch_field()

<?php  mysql_connect ($host, $user, $password)     or die ("Could not connect"); $result = mysql_db_query ("database", "select * from table")     or die ("Query failed"); # get column metadata $i = 0; while ($i < mysql_num_fields ($result)) {     echo "Information for column $i:<BR>\n";     $meta = mysql_fetch_field ($result);     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); ?>      

See also mysql_field_seek().