mysql_list_fields

(PHP 4, PHP 5, PECL mysql:1.0)

mysql_list_fields — MySQL テーブルのフィールドのリストを得る

説明

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

指定された名前のテーブルについての情報を取得します。

この関数は非推奨です。かわりに mysql_query() を利用して SHOW COLUMNS FROM table [LIKE 'name'] 文を発行することを推奨します。

パラメータ

database_name: クエリの対象となるデータベース名。
table_name: クエリの対象となるテーブル名。
link_identifier: MySQL 接続。指定されない場合、mysql_connect() により直近にオープンされたリンクが指定されたと仮定されます。そのようなリンクがない場合、引数を指定せずに mysql_connect() がコールした時と同様にリンクを確立します。リンクが見付からない、または、確立できない場合、 E_WARNING レベルのエラーが生成されます。

返り値

成功した場合に結果ポインタ resource 、失敗した場合に FALSE を返します。

返された結果は mysql_field_flags(), mysql_field_len(), mysql_field_name() そして mysql_field_type() で利用可能です。

例

例1 非推奨である mysql_list_fields() の代替例


<?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);
    }
}
?>

上の例の出力は、たとえば以下のようになります。

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

注意

注意: 下位互換のために、次の非推奨別名を使用してもいいでしょう。 mysql_listfields()

参考

mysql_list_processes

mysql_list_dbs

Last updated: Fri, 18 Jul 2008

add a note User Contributed Notes
mysql_list_fields

perwool at seznam dot cz
29-Oct-2007 03:32


Every my html table output begins with heading row containing the field names. For that purpose I accepted the short combination of MySQL function, giving me a result similar to the mysql_fetch_array() for the row of values. The following example shows the basic idea. It should be adapted for the specific use:



<?php 

//...

$field_names = array_keys( mysql_fetch_array( mysql_query( $query, $link), MYSQL_ASSOC)); 

//...

?>



The advantage of this is, that it gives the names of the result, neither the field names of the whole table. 

Please read the discussion about duplicate field names in SQL result carefully. The use, as shown in the example above, increments the pointer, hence some regular function, which does not, could be more useful :-) 



Jan

khashmeshab at yahoo dot co dot uk
12-Sep-2007 02:48


You can use this SQL command instead of 'SHOW FIELDS FROM tablename;':

'DESC tablename;'

steve at tequilasolutions dot com
12-Sep-2006 06:33


Note, using mysql_list_fields will change the currently selected database so subsequent mysql_query operations will be on the database in param 1 not the one selected with mysql_select_db

arster
15-Oct-2005 12:05


# This should also give you an array of column names

$res = mysql_query("SHOW COLUMNS FROM `my_table`");

while ($row = mysql_fetch_array($res)) $col_names[]=$row[0];

harryzhong at hotmail dot com
25-Jul-2005 09:27


Here is a simple script get names of columns in an array:



//Get names of columns in table

$field_names = array();

$res = mysql_query("SHOW COLUMNS FROM `my_table`");

for($i=0;$i<mysql_num_rows($res);$i++){

    array_push($field_names,mysql_result($res, $i));

}

rhyous at yahoo dot com
04-Jun-2005 03:22


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)



$qColumnNames = mysql_query("SHOW COLUMNS FROM table1",$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.



$qColumnNames = mysql_query("SHOW COLUMNS FROM table1",$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:



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



You can now call $row[col[firstcolumn]].  This becomes useful when you have a lot of columns.

mbevan at marginsoftware dot com
13-Nov-2003 01:40


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;

}



?>

dom at brainwaveuk dot com
19-Jul-2002 07:55


mysql_list_fields() retrieves information about the given table name but you can use something like mysql_fetch_field to retrieve the field names from a result source.

add a note

mysql_list_processes

mysql_list_dbs

Last updated: Fri, 18 Jul 2008