PDOStatement::fetchColumn

(PHP 5 >= 5.1.0, PHP 7, PHP 8, PECL pdo >= 0.9.0)

PDOStatement::fetchColumn Returns a single column from the next row of a result set

Опис

public PDOStatement::fetchColumn(int $column = 0): mixed

Returns a single column from the next row of a result set or false if there are no more rows.

Зауваження:

PDOStatement::fetchColumn() should not be used to retrieve boolean columns, as it is impossible to distinguish a value of false from there being no more rows to retrieve. Use PDOStatement::fetch() instead.

Параметри

column

0-indexed number of the column you wish to retrieve from the row. If no value is supplied, PDOStatement::fetchColumn() fetches the first column.

Значення, що повертаються

PDOStatement::fetchColumn() returns a single column from the next row of a result set or false if there are no more rows.

Увага

There is no way to return another column from the same row if you use PDOStatement::fetchColumn() to retrieve data.

Помилки/виключення

Видає помилку рівня E_WARNING, якщо атрибут PDO::ATTR_ERRMODE дорівнює PDO::ERRMODE_WARNING.

Викидає PDOException, якщо атрибут PDO::ATTR_ERRMODE дорівнює PDO::ERRMODE_EXCEPTION.

Приклади

Приклад #1 Return first column of the next row

<?php
$sth
= $dbh->prepare("SELECT name, colour FROM fruit");
$sth->execute();

print
"Fetch the first column from the first row in the result set:\n";
$result = $sth->fetchColumn();
print
"name = $result\n";

print
"Fetch the second column from the second row in the result set:\n";
$result = $sth->fetchColumn(1);
print
"colour = $result\n";
?>

Поданий вище приклад виведе:

Fetch the first column from the first row in the result set:
name = lemon
Fetch the second column from the second row in the result set:
colour = red

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