(PHP 5 >= 5.1.0, PECL pdo >= 0.1.0)
PDOStatement::bindColumn — Bind a column to a PHP variable
$column
, mixed &$param
[, int $type
[, int $maxlen
[, mixed $driverdata
]]] )PDOStatement::bindColumn() arranges to have a particular variable bound to a given column in the result-set from a query. Each call to PDOStatement::fetch() or PDOStatement::fetchAll() will update all the variables that are bound to columns.
Note:
Since information about the columns is not always available to PDO until the statement is executed, portable applications should call this function after PDOStatement::execute().
However, to be able to bind a LOB column as a stream when using the PgSQL driver, applications should call this method before calling PDOStatement::execute(), otherwise the large object OID will be returned as an integer.
column
Number of the column (1-indexed) or name of the column in the result set. If using the column name, be aware that the name should match the case of the column, as returned by the driver.
param
Name of the PHP variable to which the column will be bound.
type
Data type of the parameter, specified by the PDO::PARAM_* constants.
maxlen
A hint for pre-allocation.
driverdata
Optional parameter(s) for the driver.
成功时返回 TRUE， 或者在失败时返回 FALSE.
Example #1 Binding result set output to PHP variables
Binding columns in the result set to PHP variables is an effective way to make the data contained in each row immediately available to your application. The following example demonstrates how PDO allows you to bind and retrieve columns with a variety of options and with intelligent defaults.
<?php
function readData($dbh) {
$sql = 'SELECT name, colour, calories FROM fruit';
try {
$stmt = $dbh->prepare($sql);
$stmt->execute();
/* Bind by column number */
$stmt->bindColumn(1, $name);
$stmt->bindColumn(2, $colour);
/* Bind by column name */
$stmt->bindColumn('calories', $cals);
while ($row = $stmt->fetch(PDO::FETCH_BOUND)) {
$data = $name . "\t" . $colour . "\t" . $cals . "\n";
print $data;
}
}
catch (PDOException $e) {
print $e->getMessage();
}
}
readData($dbh);
?>
以上例程会输出：
apple red 150 banana yellow 175 kiwi green 75 orange orange 150 mango red 200 strawberry red 25