PDOStatement
PHP Manual

PDOStatement::getColumnMeta

(PHP 5 >= 5.1.0, PECL pdo >= 0.2.0)

PDOStatement::getColumnMeta Returns metadata for a column in a result set

说明

array PDOStatement::getColumnMeta ( int $column )
Warning

此函数是实验性的。 此函数的表象,包括名称及其相关文档都可能在未来的 PHP 发布版本中未通知就被修改。使用本扩展风险自担 。

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

Warning

Not all PDO drivers support PDOStatement::getColumnMeta().

参数

column

The 0-indexed column in the result set.

返回值

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.

更新日志

版本 说明
5.2.3 table field

范例

Example #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);
?>

以上例程会输出:

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

参见


PDOStatement
PHP Manual