如何将这个简单的 MySQL 示例转换为 MySQLi 面向对象的样式:
$query = mysql_query("SELECT id, name FROM fruits WHERE `group`=''");
if ($query) {
while ($row = mysql_fetch_array($query, MYSQL_ASSOC)) {
echo $row['name'];
$query2 = mysql_query("SELECT name FROM fruits WHERE `group`='{$row['id']}'");
if (mysql_num_rows($query2)) {
echo ':';
while ($row2 = mysql_fetch_array($query2, MYSQL_ASSOC)) {
echo ' '. $row2['name'] . ',';
}
mysql_free_result($query2);
echo '<br>';
}
}
mysql_free_result($query);
}
结果:
Berries: blueberry, raspberry, strawberry,
Citrus: grapefruit, lime,
Pear
数据库结构SELECT * FROM fruits
:
id | group | name
-------------------------
03E7 | | Berries
0618 | 03E7 | blueberry
051B | 03E7 | raspberry
02AA | 03E7 | strawberry
035F | | Citrus
07A5 | 035F | grapefruit
0633 | 035F | lime
05E1 | | Pear