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mysql_list_fields

(PHP 4, PHP 5)

mysql_list_fieldsList MySQL table fields

Warning

This function was deprecated in PHP 5.4.0, and it and the entire original MySQL extension was removed in PHP 7.0.0. Instead, use either the actively developed MySQLi or PDO_MySQL extensions. See also the MySQL: choosing an API guide. Alternatives to this function include:

  • SQL Query: SHOW COLUMNS FROM sometable

Description

mysql_list_fields(string $database_name, string $table_name, resource $link_identifier = NULL): resource

Retrieves information about the given table name.

This function is deprecated. It is preferable to use mysql_query() to issue an SQL SHOW COLUMNS FROM table [LIKE 'name'] statement instead.

Parameters

database_name

The name of the database that's being queried.

table_name

The name of the table that's being queried.

link_identifier

The MySQL connection. If the link identifier is not specified, the last link opened by mysql_connect() is assumed. If no such link is found, it will try to create one as if mysql_connect() had been called with no arguments. If no connection is found or established, an E_WARNING level error is generated.

Return Values

A result pointer resource on success, or false on failure.

The returned result can be used with mysql_field_flags(), mysql_field_len(), mysql_field_name() and mysql_field_type().

Examples

Example #1 Alternate to deprecated mysql_list_fields()

<?php
$result
= mysql_query("SHOW COLUMNS FROM sometable");
if (!
$result) {
echo
'Could not run query: ' . mysql_error();
exit;
}
if (
mysql_num_rows($result) > 0) {
while (
$row = mysql_fetch_assoc($result)) {
print_r($row);
}
}
?>

The above example will output something similar to:

Array
(
    [Field] => id
    [Type] => int(7)
    [Null] =>  
    [Key] => PRI
    [Default] =>
    [Extra] => auto_increment
)
Array
(
    [Field] => email
    [Type] => varchar(100)
    [Null] =>
    [Key] =>
    [Default] =>
    [Extra] =>
)

Notes

Note:

For backward compatibility, the following deprecated alias may be used: mysql_listfields()

See Also

add a note

User Contributed Notes 3 notes

up
7
mbevan at marginsoftware dot com
21 years ago
If you're willing to use a lot of functions to get a little information about fields in a table, this function is for you. If you just want to get all the information you can find, you can use this:

<?php

// Taken from: http://ca.php.net/manual/en/function.mysql-field-flags.php
// Original by: amir at scrounch dot com
// Returns the name of the fields in the primary key for a table.
// Also keeps the fields in KEY order. Handy.
function getPrimaryKeyOf($table) {
$keys = Array();

$query = sprintf("SHOW KEYS FROM `%s`", $table);
$result = mysql_query($query) or die(mysql_error());

while (
$row = mysql_fetch_assoc($result)) {
if (
$row['Key_name'] == 'PRIMARY' )
$keys[$row['Seq_in_index'] - 1] = $row['Column_name'];
}

return
$keys;
}

// Returns a bunch of information about a table...
// The name of the auto-increment field, if any, fields in the
// primary key (using the function above), and all information
// about all fields.
function getTableInformationOf($table) {
$information = array(
"auto" => "",
"primary" => array(),
"fields" => array()
);

$information['primary'] = $this->getPrimaryKeyOf($table);

$result = mysql_query("DESC `$table`");
while (
$field = mysql_fetch_assoc($result) ) {
$information['fields'][] = $field;
if (
$field['Extra'] == "auto_increment" )
$information['auto'] = $field['Field'];
}

return
$information;
}

?>
up
2
rhyous at yahoo dot com
19 years ago
To make an array containing the names of a column from a table, you use the following simple script: (Note: using table1 with three columns)

<?php
$qColumnNames
= mysql_query("SHOW COLUMNS FROM table1",$db) or die("mysql error");
$numColumns = mysql_num_rows($qColumnNames);
$x = 0;
while (
$x < $numColumns)
{
$colname = mysql_fetch_row($qColumnNames);
$col[$colname[0]] = $colname[0];
$x++;
}

print_r($col);

/* it will have the following output
Array (
[firstcolumn] => firstcolumn
[secondcolumn] => secondcolumn
[thirdcolumn] => thirdcolumn
)
*/
?>

Or you can number the columns from zero. This help when using it in conjunction with mysql_fetch_row to get an array. You don't have to remember which number of the array a certain column is.

<?php
$qColumnNames
= mysql_query("SHOW COLUMNS FROM table1",$db) or die("mysql error");
$numColumns = mysql_num_rows($qColumnNames);
$x = 0;
while (
$x < $numColumns)
{
$colname = mysql_fetch_row($qColumnNames);
$col[$colname[0]] = $x;
$x++;
}

print_r($col);

/* it will have the following output
Array (
[firstcolumn] => 0
[secondcolumn] => 1
[thirdcolumn] => 2
)
*/
?>

To use it in conjuction with mysql_fetch_row:

<?php
$row
= mysql_fetch_row("SELECT * from table1",$db) or die("mysql error");
?>

You can now call $row[col[firstcolumn]]. This becomes useful when you have a lot of columns.
up
-3
phpflow at gmail dot com
12 years ago
Below script is used to get all coloumn indormation of an table.When we are working custome ORM then we need to match the coloumn name with array keys.

<?php
function getColoumn($table) {
$result = mysql_query("SHOW COLUMNS FROM ". $table);
if (!
$result) {
echo
'Could not run query: ' . mysql_error();
}
$fieldnames=array();
if (
mysql_num_rows($result) > 0) {
while (
$row = mysql_fetch_assoc($result)) {
$fieldnames[] = $row['Field'];
}
}

return
$fieldnames;
}
?>
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