quantity20250313.php

<?php
session_start ();

include ("/home/david/MySQLTEST.php");

$db = new PDO ("mysql: host=localhost", $db_user, $db_password);

$sql = "CREATE DATABASE q20250313" . session_id () . "; ";
$db->query ($sql);

try {
    $sql = "USE q20250313" . session_id () . "; ";
    $db->query ($sql);

    $sql  = "CREATE TABLE A (x INTEGER); ";
    $sql .= "CREATE TABLE B (x INTEGER); ";
    $sql .= "CREATE TABLE C (x INTEGER); ";

    $db->query ($sql);

    for ($i = 0;  $i < 32;  $i++) {
        $sql  = "INSERT INTO A (x) VALUES (\"" . rand () % 64 . "\"); ";
        $sql .= "INSERT INTO B (x) VALUES (\"" . rand () % 32 . "\"); ";
        $sql .= "INSERT INTO C (x) VALUES (\"" . rand () % 128 . "\"); ";
        $db->query ($sql);
    }

    $sql = "SELECT x FROM (
                SELECT x FROM (SELECT x FROM A UNION SELECT x FROM B) x
                    INTERSECT
                SELECT x FROM C
            ) x ORDER BY x; ";
    $stmt = $db->query ($sql);
    while ($row = $stmt->fetch ())
        echo $row [0] . ", ";
    echo "<br>\n";
    $sql = "SELECT x FROM (
                SELECT x FROM (SELECT x FROM A INTERSECT SELECT x FROM C) x
                    UNION
                SELECT x FROM (SELECT x FROM B INTERSECT SELECT x FROM C) x
            ) x ORDER BY x; ";
    $stmt = $db->query ($sql);
    while ($row = $stmt->fetch ())
        echo $row [0] . ", ";
    echo "<br>\n";
    $sql = "SELECT x FROM (
                SELECT x FROM (SELECT x FROM B UNION SELECT x FROM C) x
                    INTERSECT
                SELECT x FROM A
            ) x ORDER BY x; ";
    $stmt = $db->query ($sql);
    while ($row = $stmt->fetch ())
        echo $row [0] . ", ";
    echo "<br>\n";
    $sql = "SELECT x FROM (
                SELECT x FROM (SELECT x FROM A INTERSECT SELECT FROM B) x
                    INTERSECT
                SELECT x FROM (SELECT x FROM A INTERSECT SELECT FROM C) x
            ) x ORDER BY x; ";
    $stmt = $db->query ($sql);
    while ($row = $stmt->fetch ())
        echo $row [0] . ", ";
    echo "<br>\n";
    $sql = "SELECT x FROM (
                SELECT x FROM (SELECT x FROM A UNION SELECT FROM C) x
                    INTERSECT
                SELECT x FROM B
            ) x ORDER BY x; ";
    $stmt = $db->query ($sql);
    while ($row = $stmt->fetch ())
        echo $row [0] . ", ";
    echo "<br>\n";
    $sql = "SELECT x FROM (
                SELECT x FROM (SELECT x FROM A INTERSECT SELECT x FROM B) x
                    UNION
                SELECT x FROM (SELECT x FROM B INTERSECT SELECT x FROM C) x
            ) x ORDER BY x; ";
    $stmt = $db->query ($sql);
    while ($row = $stmt->fetch ())
        echo $row [0] . ", ";
    echo "<br>\n";
    $sql = "DROP DATABASE q20250313" . session_id () . "; ";
    $db->query ($sql);
}
catch (Exception $e) {
    $sql = "DROP DATABASE q20250313" . session_id () . "; ";
    $db->query ($sql);
}


session_destroy ();
?>