/media/sda-magnetic/david/Dok-15-2023-11-27/informatik/www-intel-compute-stick-2022-06-13/054/quantity.php

<?php 
include ('/home/david/mysqldata.php');

$handle = mysql_connect ("localhost", $MYSQL_NAME, $MYSQL_PASSWORD);

mysql_query ("CREATE DATABASE quantity54", $handle);
mysql_select_db ("quantity54", $handle);

mysql_query ("CREATE TABLE a (x INTEGER)", $handle);
mysql_query ("CREATE TABLE b (x INTEGER)", $handle);
mysql_query ("CREATE TABLE c (x INTEGER)", $handle);

for ($i = 0;  $i < 20;  $i++) {
    mysql_query ("INSERT INTO a VALUES (\"" . rand () % 128 . "\")", $handle);
    mysql_query ("INSERT INTO b VALUES (\"" . rand () % 128 . "\")", $handle);
    mysql_query ("INSERT INTO c VALUES (\"" . rand () % 128 . "\")", $handle);

}

/* a OR b */
$result = mysql_query ("SELECT x FROM (SELECT x FROM a UNION SELECT x FROM b) x", $handle);
while ($row = mysql_fetch_row ($result))
    echo $row [0] . "<br>\n";
echo "<br><br>\n\n";
/* a AND c */
$result = mysql_query ("SELECT x FROM (SELECT x FROM a INTERSECT SELECT x FROM c) x", $handle);
while ($row = mysql_fetch_row ($result))
    echo $row [0] . "<br>\n";
echo "<br><br>\n\n";
/* (a OR b) AND c = a AND c OR b AND c*/
$result = mysql_query ("SELECT x FROM (
    SELECT x FROM (SELECT x FROM a INTERSECT SELECT x FROM c) x
    UNION 
    SELECT x FROM (SELECT x FROM c INTERSECT SELECT x FROM c) x
) x ORDER BY x", $handle);
while ($row = mysql_fetch_row ($result))
    echo $row [0] . "<br>\n";
echo "<br><br>\n\n";


$result = mysql_query ("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", $handle);
while ($row = mysql_fetch_row ($result))
    echo $row [0] . "<br>\n";
echo "<br><br>\n\n";

mysql_close ($handle);
?>