例えば「三重」と入れてみてください。学校名を部分一致で検索します(最大20件)。
<form action="schools1.php" method="post">
<p>学校名:<input name="name"></p>
</form>
<?php
if (isset($_POST['name']) && $_POST['name'] != '') {
try {
$db = new PDO('sqlite:schools.db');
$s = $db->prepare("select * from schools where name like ? limit 20");
$s->bindValue(1, "%" . $_POST['name'] . "%");
$s->execute();
$result = $s->fetchAll();
echo "<table border='1'>\n";
echo "<tr><th>学校番号</th><th>学校名</th><th>住所</th><th>郵便番号</th></tr>\n";
foreach ($result as $r) {
echo "<tr><td>", $r['id'], "</td><td>", $r['name'], "</td><td>",
$r['address'], "</td><td>", $r['zip'], "</td></tr>\n";
}
echo "</table>\n";
} catch (PDOException $e) {
echo '<p>エラー: ', $e->getMessage(), '</p>';
}
}
?>