PHP-Handbuch: Returns metadata for a column in a result set

Beschreibung

public array PDOStatement::getColumnMeta ( int $column )

Retrieves the metadata for a 0-indexed column in a result set as an associative array.

Warnung

Not all PDO drivers support PDOStatement::getColumnMeta.

The following drivers support this method:

Parameter-Liste

column: The 0-indexed column in the result set.

Rückgabewerte

Returns an associative array containing the following values representing the metadata for a single column:

**Column metadata**
Name	Value
native_type	The PHP native type used to represent the column value.
driver:decl_type	The SQL type used to represent the column value in the database. If the column in the result set is the result of a function, this value is not returned by PDOStatement::getColumnMeta.
flags	Any flags set for this column.
name	The name of this column as returned by the database.
table	The name of this column's table as returned by the database.
len	The length of this column. Normally -1 for types other than floating point decimals.
precision	The numeric precision of this column. Normally 0 for types other than floating point decimals.
pdo_type	The type of this column as represented by the PDO::PARAM_* constants.

Returns FALSE if the requested column does not exist in the result set, or if no result set exists.

Changelog

Version	Beschreibung
5.4.0	PDO_DBLIB driver support added
5.2.3	table field

Beispiele

Beispiel #1 Retrieving column metadata

The following example shows the results of retrieving the metadata for a single column generated by a function (COUNT) in a PDO_SQLITE driver.


<?php
$select = $DB->query('SELECT COUNT(*) FROM fruit');
$meta = $select->getColumnMeta(0);
var_dump($meta);
?>

Das oben gezeigte Beispiel erzeugt folgende Ausgabe:

array(6) {
  ["native_type"]=>
  string(7) "integer"
  ["flags"]=>
  array(0) {
  }
  ["name"]=>
  string(8) "COUNT(*)"
  ["len"]=>
  int(-1)
  ["precision"]=>
  int(0)
  ["pdo_type"]=>
  int(2)
}

Siehe auch

PDOStatement::columnCount
PDOStatement::rowCount