PHP Mysql Tutorials, Function, mysql_list

Topic

What is mysql_list_fields() function in PHP?
How does mysql_list_fields() works?

Explanation

The mysql_list_fields() function list given MySQL table fields.

Syntax

resource mysql_list_fields ( string database_name, string table_name [, resource link_identifier])

Returns result pointer resource on success, or FALSE on failure.

mysql_list_fields() retrieves information about the given table name, when the database and the table name is passed as arguments. This function returns a result pointer to retrieve field information, which can be used with mysql_field_flags() to list field flags of the specified field, mysql_field_len() to list maximum length of the specified field, mysql_field_name() to list name of the specified field index, and mysql_field_type() to list field type of specified fields.

This function is deprecated. It is preferable to use mysql_query() function to execute SQL query 'SHOW COLUMNS FROM table_name [LIKE 'name'] to retrieve field information of given table .

Example

<?php

//Attempt to connect to the default database server

$link = mysql_connect("mysql_host", "mysql_user", "mysql_password")
or die ("Could not connect");

//returns result pointer of field informatin

$fields = mysql_list_fields("database1", "table1", $link);

//returns number of fields

$columns = mysql_num_fields($fields);

//list name of fields returned by result pointer

for ($i = 0; $i < $columns; $i++) {
echo mysql_field_name($fields, $i) . "\n";
}

?>

Above code returns a result pointer to retrieve field information using mysql_list_fields function for a given connection $link. mysql_num_fields function is used to fetch the number of returned fields and fields names returned by result pointer is listed by using mysql_field_name function.

RESULT:

field1
field2
field3...