PDOStatement::columnCount

Returns the number of columns in the result set

Description

public int PDOStatement::columnCount()

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.

Parameters

This function has no parameters.

Return Values

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

Errors/Exceptions

Emits an error with level E_WARNING if the attribute PDO::ATTR_ERRMODE is set to PDO::ERRMODE_WARNING.

Throws a PDOException if the attribute PDO::ATTR_ERRMODE is set to PDO::ERRMODE_EXCEPTION.

Examples

Example #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";

?>

The above example will output:

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