<html>
<?php
//$pdo = new PDO('sqlite::memory:'); //内存中的数据库
$pdo = new PDO('sqlite:mydb.db');
$pdo->exec('CREATE TABLE test(ID INT NOT NULL PRIMARY KEY, Field VARCHAR(12) NULL);');
$stmt = $pdo->prepare('INSERT INTO test(ID, Field) VALUES(?, ?)');
$one = 1;
$two = 2;
$null = NULL;
// Try with PDO_PARAM_NULL
$stmt->bindParam(1, $one, PDO::PARAM_INT); //绑定参数
$stmt->bindParam(2, $null, PDO::PARAM_STR);
assert($stmt->execute());
// Try with PDO_PARAM_STR
$stmt->bindParam(1, $two, PDO::PARAM_INT);
$stmt->bindParam(2, $null, PDO::PARAM_STR);
assert($stmt->execute());
// Check we have rows..
$stmt = $pdo->prepare('SELECT * FROM test');
assert($stmt->execute());
var_dump($stmt->fetchAll());
// Check we have rows with field is null
echo '<hr />';
$stmt = $pdo->prepare('SELECT * FROM test WHERE Field IS NULL');
assert($stmt->execute());
var_dump($stmt->fetchAll()); //显示查询结果
?>
</html>