mysql_field_type

(PHP 4, PHP 5)

mysql_field_type — 取得结果集中指定字段的类型

说明

mysql_field_type ( resource $result , int $field_offset ) : string

mysql_field_type() 和 mysql_field_name() 函数相似。参数完全相同，但返回的是字段类型而不是字段名。字段类型有"int"，"real"，"string"，"blob"以及其它，详见 » MySQL 手册。

Example #1 mysql_field_type() 例子


<?php
    mysql_connect("localhost", "mysql_username", "mysql_password");
    mysql_select_db("mysql");
    $result = mysql_query("SELECT * FROM func");
    $fields = mysql_num_fields($result);
    $rows   = mysql_num_rows($result);
    $table = mysql_field_table($result, 0);
    echo "Your '".$table."' table has ".$fields." fields and ".$rows." record(s)\n";
    echo "The table has the following fields:\n";
    for ($i=0; $i < $fields; $i++) {
        $type  = mysql_field_type($result, $i);
        $name  = mysql_field_name($result, $i);
        $len   = mysql_field_len($result, $i);
        $flags = mysql_field_flags($result, $i);
        echo $type." ".$name." ".$len." ".$flags."\n";
    }
    mysql_free_result($result);
    mysql_close();
?>

以上例子将产生如下输出：

Your 'func' table has 4 fields and 1 record(s)
The table has the following fields:
string name 64 not_null primary_key binary
int ret 1 not_null
string dl 128 not_null
string type 9 not_null enum

为向下兼容仍然可以使用 mysql_fieldtype()，但反对这样做。

参数

result: resource 型的结果集。此结果集来自对 mysql_query() 的调用。
field_offset: 数值型字段偏移量。 field_offset 从 0 开始。如果 field_offset 不存在，则会发出一个 E_WARNING 级别的错误

返回值

The returned field type will be one of "int", "real", "string", "blob", and others as detailed in the » MySQL documentation.

范例

Example #2 mysql_field_type() example


<?php
mysql_connect("localhost", "mysql_username", "mysql_password");
mysql_select_db("mysql");
$result = mysql_query("SELECT * FROM func");
$fields = mysql_num_fields($result);
$rows   = mysql_num_rows($result);
$table  = mysql_field_table($result, 0);
echo "Your '" . $table . "' table has " . $fields . " fields and " . $rows . " record(s)\n";
echo "The table has the following fields:\n";
for ($i=0; $i < $fields; $i++) {
    $type  = mysql_field_type($result, $i);
    $name  = mysql_field_name($result, $i);
    $len   = mysql_field_len($result, $i);
    $flags = mysql_field_flags($result, $i);
    echo $type . " " . $name . " " . $len . " " . $flags . "\n";
}
mysql_free_result($result);
mysql_close();
?>

以上例程的输出类似于：

Your 'func' table has 4 fields and 1 record(s)
The table has the following fields:
string name 64 not_null primary_key binary
int ret 1 not_null
string dl 128 not_null
string type 9 not_null enum

注释

Note:
为了向下兼容，可以使用下列已废弃的别名： mysql_fieldtype()

参见

mysql_field_name() - 取得结果中指定字段的字段名
mysql_field_len() - 返回指定字段的长度

User Contributed Notes

fred at dinkler dot com 08-Feb-2007 11:52


In MySQL 4.1.x, the four TEXT types (TINYTEXT, TEXT, MEDIUMTEXT, and LONGTEXT) return 'blob" as field types, not "string".

c dot futterlieb at bluewin dot ch 10-Dec-2006 06:06


Additional to the note below:

If you're using the "SHOW FIELDS" syntax, be sure that you're adding the table name instead of the db name in the "FROM" parameter:



<?php

$result = mysql_query("SHOW FIELDS FROM table");

?>



Also possible:



<?php

$result = mysql_query("SHOW FIELDS FROM table.db");

?>



or this:



<?php

$result = mysql_query("DESCRIBE table");

?>

http://dev.mysql.com/doc/refman/5.1/en/describe.html

fusionstream at gmail dot com 17-Sep-2006 09:19


krang at krang dot org dot uk

Condensed version of what KRANG said.



To get info on the MYSQL field type, use this code



<?

$result = mysql_query("SHOW FIELDS FROM db_name");



$i = 1;

while ($row = mysql_fetch_array($result)) { //go through one field at a time

  echo "Field $i: ";

  print_r($row) //display all information about A field which can be accessed thru the "$row" array.

  $i++;

}

?>



Will display something like:

Field 1: Array ( [Field] => SN [Type] => mediumint(8) unsigned [Null] => [Key] => PRI [Default] => [Extra] => auto_increment ) , SN, mediumint(8) unsigned

Field 2: Array ( [Field] => ENTITY_ID [Type] => varchar(20) [Null] => [Key] => [Default] => [Extra] => ) , ENTITY_ID, varchar(20)

mariob at menta dot net 07-Nov-2003 12:21


For version 4.3.4, types returned are:



STRING, VAR_STRING: string

TINY, SHORT, LONG, LONGLONG, INT24: int

FLOAT, DOUBLE, DECIMAL: real

TIMESTAMP: timestamp

YEAR: year

DATE: date

TIME: time

DATETIME: datetime

TINY_BLOB, MEDIUM_BLOB, LONG_BLOB, BLOB: blob

NULL: null

Any other: unknown

swalif_mesa at hotmail dot com 09-Jul-2003 10:38


Hmm for the previous comment, note that SHOW FIELDS is an alias of SHOW COLUMNS. Very useful if you need to search the mysql-documentation. Here is the link anyway...

http://www.mysql.com/doc/en/SHOW_DATABASE_INFO.html

krang at krang dot org dot uk 10-Mar-2002 06:13


The field type returns what PHP classifies the data found in the field, not how it is stored in the database; use the following example to retrieve the MySQL information about the field....



$USERNAME = '';

$PASSWORD = '';



$DATABASE = '';

$TABLE_NAME = '';



mysql_connect('localhost', $USERNAME, $PASSWORD)

    or die ("Could not connect");



$result = mysql_query("SHOW FIELDS FROM $DATABASE.$TABLE_NAME");



$i = 0;



while ($row = mysql_fetch_array($result)) {

  echo $row['Field'] . ' ' . $row['Type'];

}