PDOStatement::columnCount

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

PDOStatement::columnCount — Returns the number of columns in the result set

Описание

int PDOStatement::columnCount ( void )

Use PDOStatement::columnCount() to return the number of columns in the result set represented by the PDOStatement object.

If the PDOStatement object was returned from PDO::query(), the column count is immediately available.

If the PDOStatement object was returned from PDO::prepare(), an accurate column count will not be available until you invoke PDOStatement::execute().

Возвращаемые значения

Returns the number of columns in the result set represented by the PDOStatement object. If there is no result set, PDOStatement::columnCount() returns 0.

Примеры

Пример #1 Counting columns

This example demonstrates how PDOStatement::columnCount() operates with and without a result set.


<?php
$dbh = new PDO('odbc:sample', 'db2inst1', 'ibmdb2');

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

/* Count the number of columns in the (non-existent) result set */
$colcount = $sth->columnCount();
print("Before execute(), result set has $colcount columns (should be 0)\n");

$sth->execute();

/* Count the number of columns in the result set */
$colcount = $sth->columnCount();
print("After execute(), result set has $colcount columns (should be 2)\n");

?>

Результат выполнения данного примера:

Before execute(), result set has 0 columns (should be 0)
After execute(), result set has 2 columns (should be 2)

Смотрите также

PDO::prepare() - Prepares a statement for execution and returns a statement object
PDOStatement::execute() - Executes a prepared statement
PDOStatement::rowCount() - Returns the number of rows affected by the last SQL statement